ThinkWiki - User contributions [en]

Talk:How to configure the TrackPoint

2008-12-31T17:11:07Z

Telofy: /* /sys-configuration files */

==== /sys-configuration files ====
where can i find documentation of the other files (thresh, upthresh, skipback, reach, inertia...)? [[User:Blerp|Blerp]] 01:01, 9 March 2007 (CET)
:I second that question. --[[User:Telofy|Telofy]] 18:11, 31 December 2008 (CET)

==== shifting /sys-paths ====
2007-03-13
On my Thinkpad R60 with kernel 2.6.20, the path is {{path|/sys/devices/platform/i8042/serio1/serio2}}.

On {{Fedora}} 5, with kernels 2.6.15 and forward, the path does not include
{{path|serio2}}; it stops at {{path|serio0}}.

Same thing on a {{Ubuntu}} Dapper install on an {{X31}}, again with kernel 2.6.15 (maybe that's the reason? [[User:Piccobello|Piccobello]] 17:02, 26 November 2006 (CET)).

2006-07-18
On {{Fedora}} 5, with kernels 2.6.16 and forward, the path is {{path|/sys/devices/platform/i8042/serio0/serio2}}

2005-11-07
OpenSuSE 10.0 has a kernel based on 2.6.13 (probably heavily patched), but the directory /sys/devices/platform/i8042/serio0/serio2 does not exist.
instead, it looks like this:
hoppetosse:/sys/devices/platform/i8042/serio0 # ls -l
total 0
-rw-r--r-- 1 root root 4096 Nov 7 18:38 bind_mode
lrwxrwxrwx 1 root root 0 Nov 7 18:38 bus -> ../../../../bus/serio
-r--r--r-- 1 root root 4096 Nov 7 18:38 description
lrwxrwxrwx 1 root root 0 Nov 7 18:38 driver -> ../../../../bus/serio/drivers/psmouse
--w------- 1 root root 4096 Nov 7 18:38 drvctl
drwxr-xr-x 2 root root 0 Nov 7 18:38 id
-r--r--r-- 1 root root 4096 Nov 7 18:38 modalias
drwxr-xr-x 2 root root 0 Nov 7 18:38 power
-rw-r--r-- 1 root root 4096 Nov 7 18:38 protocol
-rw-r--r-- 1 root root 4096 Nov 7 18:38 rate
-rw-r--r-- 1 root root 4096 Nov 7 18:38 resetafter
-rw-r--r-- 1 root root 4096 Nov 7 18:38 resolution
"description" says it's an "i8042 Aux Port". The page [[Patch to enable advanced trackpoint configuration]] seems to imply that a kernel patch is needed in order to get those features... this needs clarification.
hmm. where can i find out whether "drvctrl" is what i'm looking for and what options it takes? guess it's back to RTFS...

2005-10-06
It seems that new version of the patch ( 2.6.12 at least ), the press to select entry in /sys is named "press_to_select" and not "ptson". I changed the page accordingly so that it complies with the [[Patch to enable advanced trackpoint configuration]] page.
If you use an older version try :

====Press to Select====
Press to Select allows you to tap the control stick which will simulate a left click. You can enable this feature by typing the following in to a terminal (you may need to be root):

:{{cmdroot|echo 1 > /sys/devices/platform/i8042/serio0/ptson}}

Press to Select should now be enabled. You can disable it in a similar manner:

:{{cmdroot|echo 0 > /sys/devices/platform/i8042/serio0/ptson}}

Where do I have to put this script (which should automate this), so that it is executed on startup (I have kubuntu (feisty) runing)? Samba

==== No mouse in {{Fedora}} Core 6 ====
FC6 makes an X11/xorg.conf file with no mouse section, so it's not clear how to make the TrackPoint work for scrolling. Any ideas? --[[User:Whizkid|Whizkid]] 17:36, 4 December 2006 (CET)

==== TrackPoint scrolling inverted in Firefox ====
Running Ubuntu Feisty, Firefox 2.0.0.3, I edited /etc/X11/xorg.conf like described in the article and set mousewheel.horizscroll.withnokey.action = 0; in Firefox.
Scrolling works perfectly in other applications. Up-Down scrolling in Firefox, too, but right-left is inverted (only in Firefox). Does anybody have an idea why this could be? [[User:Tec|Tec]] 11:15, 30 March 2007 (CEST)

Yes: you have to configure mousewheel.horizscroll.withnokey.numlines as well. I have the value set to 1, but you may need to set it to -1.
There is also a mousewheel.horizscroll.withnokey.sysnumlines setting, which you must set to false. --[[User:RichardNeill|RichardNeill]] 03:22, 4 April 2007 (CEST)

Thanks a lot. mousewheel.horizscroll.withnokey.sysnumlines was set to false correctly, but mousewheel.horizscroll.withnokey.numlines was set to -1 as a standard setting. Switched to 1 and it works perfectly :-) BTW, is there a good explanation available in the net, what all those parameters of about:config mean? I searched for it and didn't find anything :-( [[User:Tec|Tec]]

==== Sensitivity and Speed settings under Gutsy Gibbon ====

Sensitivity and speed value editing seem broken in gutsy.
Its no writeable even as root. Tools like configure-trackpoint do not start arguing a lack of root tights.

:Hm, I just installed the deb 0.6-1 available at sourceforge and sudo configure-trackback works for me. Maybe you'd better ask in some forum or file a bug to find out why it's not working on your machine? [[User:Tec|Tec]]

::I confirm that even root can not edit the config files with an editor (vim or nano). But the echo > file works fine.
::{{cmdroot|echo -n 120 > /sys/devices/platform/i8042/serio1/serio2/speed}}
:: I have put these echo in a script executed by root at bootime with a @reboot entry in the root's crontab. Should also work with a call to that script in /etc/bootmisc.sh
::[[User:Ripat|Ripat]] 10:20, 6 January 2008 (CET)

:::Same on my machine. Config files are not writable with an editor, but echo > file works. {{cmduser|sudo configure-trackpoint}} works, too (sorry, I misspelled this before) [[User:Tec|Tec]] 16:00, 12 January 2008 (CET)

== No scroll in Ubuntu 7.10 without UltraNav installed in Windows Vista ==

I could not get trackpoint scroll working in Ubuntu 7.10 (Gutsy Gibbon) on my Z61t using the xorg.conf modifications listed here until I installed the UltraNav Utility on Windows Vista (dual-boot configuration). Scrolling worked fine without the UltraNav utility and with just the UltraNav driver on Windows. It's weird to me that installing the UltraNav utility in Vista would have an effect on Ubuntu. (I know it's not a coincidence because I ran into it once before.) Any explanation for this strangeness?
--[[User:Threexk|Threexk]] 04:05, 18 February 2008 (CET)

Install Ubuntu 8.10 (Intrepid Ibex) on a ThinkPad T400

2008-12-08T15:09:28Z

Telofy: /* Menu-Key */

[[:Category:T400|T400]] '''Site under construction. You are invited building an useful guidance!'''

==Before Installation==

Before you can start Ubuntu from CD or USB you have to change two BIOS settings:
* Change to Internal or ATI Graphics with Config --> Display --> Graphics Device --> [Integrated graphics] or [Discrete Graphics]
* Disable OS Detection for Switchable Graphics. Otherwise it will mysteriously switch back to Switchable Graphics.

Now you can boot your Live-CD, connect to Wireless Lan, and install the OS.

==What works out of the box?==

*Wireless with iwlagn driver ([[Intel WiFi Link 5100/5300 WLAN controller]])
**G mode + WEP and WPA2 PSK (If you have the ThinkPad 11b/g Wireless LAN mini PCI Express Adapter III (Aetheros Chipset), see below!)
**with status LED and everything!
*Bluetooth
**Even with [[Bluetooth Laser Mouse]]
*[[Ethernet Controllers#Intel Gigabit (10/100/1000)|Intel Gigabit Ethernet Controller]]
*Intel driver for Integrated Graphics ([[Intel Integrated Intel GMA 4500MHD]])
** with 3D acceleration out-of-the-box
** VGA output - mirrored and extended desktop both work, but might need to run the following to enable 1600x1200 resolution
{{cmduser|sudo dpkg-reconfigure -phigh xserver-xorg}}
*ATI [[fglrx]] driver for Discrete Graphics ([[ATI Mobility Radeon 3470 graphics]])
**To enjoy 3D acceleration, you have to install the proprietary [[fglrx]] Driver. (for example with the jockey-gtk tool)
*Touchpoint and Trackpad
**Including scroll at the right side of the pad by default. (for scrolling with the middle mouse button, see below!)
*Optical drive
**Not tested burning yet
*Sound card
**To use your internal microphone you have to change to "HDA Intel CONEXANT Analog (ALSA)" in audio-settings.
*built-in webcam with Skype
*7-in-1 card reader from Ricoh (MMC, Memory Stick, Mem Stick Pro, SD, SDHC, XD, XD Type H Memory)
**Only tested SD cards.
*Control buttons/Hotkeys
**Volume control buttons
**Screen brightness control (but changing brightness is a little bit diffuse. It's getting brighter but on maximum it changes to nearly lowest and get brighter again.)
**Thinklight control
**WLAN/BT/OFF toggle (Fn+F5 and mechanical toggle)
**Media player control
*Some ACPI features
**Battery status, power graphs and history (tested with an single 6-Cell battery)
**Lid states and events

==What needs some Tweaks?==

====[[ThinkVantage Button]] {{ibmkey|ThinkVantage|#495988}}====

Edit the file /usr/share/hotkey-setup/ibm.hk with adding this line:

setkeycodes e017 148 #thinkpad button

You have to restart, then you refer a program with the "System -> Preferences -> Keyboard Shortcuts"-Menu (eg. Terminal, Firefox,...).

====Internal LCD Resolution Fix====

The native screen resolution of 1440x900 is not detected automatically. The problem is that a secondary cloned display is set to 1360x768, and is being displayed on the integrated screen. Disable screen cloning, and disable the secondary display to fix the problem. For a complete fix, a restart of X is required (CTRL+ALT+BACKSPACE) is required, and when logging in again, you may need to fix your dock icon positions.

However, GDM still displays at either 1152x864 or 1360x768, creating a fuzzy image, or leaving borders at right and bottom, respectively. But it isn't a problem after logging in.

'''UPDATE:'''The solution posted above was too sparse for me. Instead, I found a new driver and compviz packages that fixed the problem using the v.2.5.0 of the intel drivers that are available here:https://launchpad.net/~thjaeger/+archive

make a back up of your /etc/apt/sources.list, i.e.

sudo cp /etc/apt/sources.list /etc/apt/sources.list.bak

Then add the following lines at the end of the /etc/apt/sources.list:

deb http://ppa.launchpad.net/thjaeger/ubuntu intrepid main

deb-src http://ppa.launchpad.net/thjaeger/ubuntu intrepid main

which you can edit using:

sudo gedit /etc/apt/sources.list

once you've closed gedit, update the list of updates by typing:

sudo apt-get update

this will update the package db, and you should see the 'package update' icon light up. Open that up, and apply the updates. Alternately, you can open it via System->Administration->Update Manager

Once the updates are applied, you will need to revert your /etc/X11/xorg.conf file if you've made any changes to it. You can do this via:

sudo dpkg-reconfigure -phigh xserver-xorg

Finally press ctrl-alt-backspace to restart the X-server.

Now, once you've logged back in, under System->Preferences->Screen Resolution, you should see 1440x900 listed.

====Shutdown freezes sometimes====

It seems that ALSA has problems to shut down if network devices are still active.
You can force ALSA during its unloading to disable the networking first (remember to backup your files!):
sudo gedit /etc/init.d/alsa-utils
Search for "stop)" and add immediately below:

ifconfig eth0 down
ifconfig wlan0 down

'''NOTE''' - This doesn't seem to be a problem with Madwifi drivers, it is created by the Intel wireless card?

Now your shutdown should go smoothly.

====VGA Output Resolution Fix====

To enable 1600x1200 resolution to show up, run
{{cmduser|sudo dpkg-reconfigure -phigh xserver-xorg}}

====ThinkPad 11b/g Wireless LAN mini PCI Express Adapter III (Atheros AR5007EG/AR2425 Chipset)====

There are two options for drivers here, the ath5k project, or older Madwifi drivers. The Madwifi drivers are based on the older, closed source HAL by Atheros, and the ath5k driver are based on the newer open source HAL by Atheros. Note that you should not enable more than one Atheros driver, or they will conflict with each other (this includes ath5k, ath9k, and Madwifi). If you need both BG & N support, do not use ath5k & ath9k, use Madwifi instead (only applicable if you are running multiple wireless cards).

'''NOTE:''' One user (with the a B/G card) reports that wireless performance was awful with the FOSS ath5k driver, but smooth and nice with Madwifi. YMMV - Also, the ath5k do not correctly detect hardware settings such as txpower.

'''NOTE 2:''' Due to a conflict, in order to achieve a stable connection it may be necessary to remove linux-restricted-modules beforehand using the following command: "sudo update-rc.d -f linux-restricted-modules-common remove"
http://madberry.org/2008/11/how-to-get-atheros-ar242x-to-work-on-810-intrepid-ibex/

'''Installing the ath5k drivers from the compat-wireless package'''

Original discussion thread: [http://ubuntuforums.org/showpost.php?p=6071960&postcount=2]

1. Become the super user of the system:

{{cmduser|sudo su}}

*NOTE: Becareful here, as you have complete access to the system, and can do damage if careless. Optionally, you can work as a normal user, and preface each command with sudo.

Disable any currently running Madwifi drivers by running this in the terminal:

{{cmdroot|rmmod ath_pci; rmmod ath_hal}}

3. These drivers require source compilitation, so the build-essential package is required:

{{cmdroot|apt-get install build-essential}}

4. Enter the /usr/src directory, and download the source package:

{{cmdroot|cd /usr/src; wget http://wireless.kernel.org/download/compat-wireless-2.6/compat-wireless-2008-10-31.tar.bz2}}

5. Extract the source and enter the directory:

{{cmdroot|tar xjvf compat-wireless-2008-10-31.tar.bz2; cd compat-wireless-2008-10-31}}

6. Take a quick look at the README:

{{cmdroot|less README}}

7. Begin the compiliation process

{{cmdroot|make}}

8. Next, disable any active wireless connections, and run a script to make sure all wireless drivers that are going to be replaced are unloaded:

{{cmdroot|make unload}}

9. Install the drivers:

{{cmdroot|make install}}

10. If everything completed without errors, load the ath5k module:

{{cmdroot|modprobe ath5k}}

11. Check to make sure the new drivers detected the wireless card (you may need to adjust the interface name if you have several wireless cards):

{{cmdroot|ifconfig wlan0 up; iwconfig}}

NOTE: When I first installed these drivers, they were unable to bring the MAC chip up, and needed a restart.

12. Clean the src directory

{{cd /usr/src; rm compat-wireless-2008-10-31}}

NOTE: You can also delete the compat-wireless-2008-10-31/ folder if you need to recover the space, but it is useful to keep because the Makefile has a 'make uninstall' switch.

13. Last, blacklist any other drivers that may interfere with the new ath5k drivers:

{{echo "blacklist ath_pci" >> /etc/modprobe.d/blacklist; echo "blacklist ath_hal" >> /etc/modprobe.d/blacklist}}

'''Installing the Madwifi drivers:'''

The following instructions were originally found here [http://ubuntuforums.org/showpost.php?p=5711824&postcount=6]:

1. Under System/Administration/HarwareDrivers disable "Support for Atheros 802.11 wireless LAN cards

2. Reboot

3. The kernel headers and the compiler are needed to build this driver so install build-essential. In a terminal window (Applications/Accessories/Terminal) enter:

{{cmduser|sudo apt-get install build-essential}}

4. Install Subversion

{{cmduser|sudo apt-get install subversion}}

5. Checkout the Madwifi drivers to a directory on your local disk

{{cmduser|cd~}}
{{cmduser|mkdir madwifi}}
{{cmduser|cd madwifi}}
{{cmduser|svn co https://svn.madwifi.org/madwifi/branches/madwifi-hal-0.10.5.6}}

6. Build the drivers

{{cmduser|cd madwifi-hal-0.10.5.6}}
{{cmduser|make}}

7. Install the drivers

{{cmduser|make install}}

8. Add the Atheros kernel module to the list of modules to be automatically loaded at boot by adding "ath_pci" (without the quotes) to the end of the /etc/modules file and save the file

{{cmduser|sudo gedit /etc/modules}}

9. Now you can reboot and it should work. To get it working without a reboot you need to load the module manually you can use

{{cmduser|sudo modprobe ath_pci}}

====Scrolling with Trackpoint====

Create a new file called /etc/hal/fdi/policy/mouse-wheel.fdi typing:

{{cmduser|sudo gedit /etc/hal/fdi/policy/mouse-wheel.fdi}}

And fill it with this code:

<match key="info.product" string="TPPS/2 IBM TrackPoint">
<merge key="input.x11_options.EmulateWheel" type="string">true</merge>
<merge key="input.x11_options.EmulateWheelButton" type="string">2</merge>
<merge key="input.x11_options.XAxisMapping" type="string">6 7</merge>
<merge key="input.x11_options.YAxisMapping" type="string">4 5</merge>
<merge key="input.x11_options.ZAxisMapping" type="string">4 5</merge>
<merge key="input.x11_options.Emulate3Buttons" type="string">true</merge>
</match>

Source: [http://psung.blogspot.com/2008/09/scrolling-with-thinkpads-trackpoint-in.html]

(Based on code from [http://mvogt.wordpress.com/2008/08/15/xorg-evdev-and-emulatewheel/ Michael Vogt] and adapted to support both vertical and horizontal scrolling.)

'''Note:''' If you change to another Shell (<ctrl><alt>F1 etc) the Trackpoint does not scroll anymore. Restarting the Xserver works and can most easily done by choosing "switch user" and than log in again. All programs stay open and it does not take much time.

====Enabling Touchpad on/off key====
Source: [[https://help.ubuntu.com/community/SynapticsTouchpad#shmconfig]]
The SHMConfig is now controlled through hal. In the past this was done through xorg.conf

You have to add the file
{{cmduser|sudo gedit /etc/hal/fdi/policy/shmconfig.fdi}}
with the following content:
<?xml version="1.0" encoding="ISO-8859-1"?>
<deviceinfo version="0.2">
<device>
<match key="input.x11_driver" string="synaptics">
<merge key="input.x11_options.SHMConfig" type="string">True</merge>
</match>
</device>
</deviceinfo>

After this change please reboot. Restarting hal doesn't help.

==What doesn't work at the moment?==

====[[Integrated Fingerprint Reader]]====

Theres a new chipset build in, the "AuthenTec AES2810". So neither the [http://thinkfinger.sourceforge.net thinkfinger] nor the [http://www.reactivated.net/fprint/wiki/Main_Page fprint] Project support this Device at the moment.

lsusb:
Bus 002 Device 004: ID 08ff:2810 AuthenTec, Inc.

Daniel from fprint Project wrote in their mailing list, that support for our device is in development!
For more information look here: [http://reactivated.net/fprint/wiki/Unsupported_devices fprint Unsupported devices]

====[[Switchable Graphics]]====

I installed Ubuntu 8.10 with the on-board Intel Graphic chip. So 3D acceleration works out-of-the-box.

Then I booted with the ATI Graphics, which was no problem, because the [[radeon]] driver works very well, but only in 2D.

After installing [[fglrx]] packages, jockey also found out, that proprietary drivers are available. So i let him configure my xorg.conf:

Section "Monitor"
Identifier "Configured Monitor"
EndSection

Section "Screen"
Identifier "Default Screen"
Monitor "Configured Monitor"
Device "Configured Video Device"
DefaultDepth 24
EndSection

Section "Module"
Load "glx"
EndSection

Section "Device"
Identifier "Configured Video Device"
EndSection

Section "Device"
Identifier "ATI Technologies Inc Mobility Radeon HD 3400 Series"
BusID "PCI:01:00.0"
Driver "fglrx"
EndSection

After reboot also Compiz works (but not so smooth as with Intel, i allege)

'''Problem:''' Strating up with integrated graphic again, no 3D desktop works. After removing all [[fglrx]] packages, Compiz normally works.

So i changed my xorg.conf using the [[radeon]] driver, succeeding to have 3D on onboard Graphics and 2D on ATI Graphics.

I also tried [[radeonhd]] driver, which does not work.

'''Note 1:''' I got tired of going in to BIOS to switch chipsets, so I explicitly set the BusID in xorg.conf. The problem with this approach is that power consumption doubles, even when you are not using the discrete graphics card. I had 28W consumption when in switchable graphics mode, and 16W consumption when I configured "Integrated graphics" in BIOS.

'''Note 2:''' fglrx diverts libGL.so.1.2 that is installed by mesa. This means that you can't simply swap xorg.conf files and kernel modules, you need to replace libGL.so.1.2 with the proper one if you want restart X with a certain chipset.

{{Todo|Maybe anybody can get both working!}}

====Suspend/Hibernate====

Neither Suspend nor Hibernate work out of the box. They fall asleep, but when waking up only the mousepointer is on the black screen, put neither keyboard, nor mouse showing response.

Here's a [http://ubuntuforums.org/showthread.php?p=6057496 Ubuntu forum discussion thread] about the problem!

Petri K posted a workaround, to get suspend and hibernate working:

"I would say that this is a classical multiprocessor concurrency control problem! Disabling all but one core makes the bug disappear.
Here is my suggestion for a workaround. Save in /etc/pm/sleep.d/00CPU with 755 permissions.
Note that it has to be called 00CPU so that it gets executed before and after anything else."

Open Terminal and type:

{{cmduser|sudo gedit /etc/pm/sleep.d/00CPU}}

Copy the following Code into gedit and save the file!

#!/bin/sh
# Workaround for concurrency bug in xserver-xorg-video-intel 2:2.4.1-1ubuntu10.
# Save this as /etc/pm/sleep.d/00CPU

. "${PM_FUNCTIONS}"

case "$1" in
hibernate|suspend)
for i in /sys/devices/system/cpu/cpu*/online ; do
echo 0 >$i
done
;;
thaw|resume)
sleep 10 # run with one core for 10 secs
for i in /sys/devices/system/cpu/cpu*/online ; do
echo 1 >$i
done
;;
*)
;;
esac

Then close gedit and copy this line into the terminal to set permission 755 (read, write and execute):

{{cmduser|sudo chmod 755 /etc/pm/sleep.d/00CPU}}

After reboot suspend and hibernate should work for you, because there is only one core running while doing this events.

====Menu-Key====

I changed keyboard modell to "IBM Thinkpad R60/T60/R61/T61" using the "German Dead acute" Layout.

But also with these settings my menu-key does not work.
I tried to refer it with Firefox using the keyborad shortcuts-tool. It writes: "XF86WakeUp"

'''Problem:''' The FN-Key also writes "XF86WakeUp", which is not so practical, so I removed allocation!

{{Todo| Is ist possible to have a real menu-key?}}

==Not tested yet==

====[[Active Protection System]]====

There is no patch for Kernel 2.6.27-7 at the moment to use [[HDAPS]]. See also [[How to protect the harddisk through APS]].

====VGA/HDMI====
*NEC MultiSync LCD 2190UX - VGA tested and working in mirrored and extended desktop modes (had to run {{cmduser|sudo dpkg-reconfigure -phigh xserver-xorg}} to get 1600x1200 resolution to show up)
{{todo|please test other external monitors!}}

[[Category:T400]][[Category:Ubuntu]][[Category:Ubuntu_8.10]]

How to reduce power consumption

2008-12-06T18:24:58Z

Telofy: /* Kernel boot and module loading options */ (Great and apt pun though)

Reducing system power consumption will extend battery life, reduce system
temperature and (on some models) reduce system fan noise.
Power consumption can be greatly improved from a stock distribution configuration
to a fine tuned system. The general rules are :
* Unload drivers for unused devices (ie. USB 1.1, Yenta/PCMCIA, Wireless, IRDA, Bluetooth, ...)
* Reduce polling on devices (drives, USB subsystem, nvram, use SATA AN, ...)
* Reduce hard drive activity
* Reduce LCD brightness to the minimum you can stand
* Reduce CPU wakeups, so it can stay longer in deep power saving c-states
* Make use of every hardware devices availables power saving features (AHCI ALPM, USB autosuspend, Alsa and Wireless powersaving modes, HPET timers, ...)

==Tools==
Arjan van de Ven's [[PowerTOP]] utility
is a gold mine to improve energy efficiency, but is almost only CPU-oriented. This tool helps to easily detect
the top power offenders, both userland and kernel modules, which prevent the use of CPU power saving mechanisms and sometime suggest
fixes accordingly.
PowerTOP users collected some [http://www.lesswatts.org/projects/powertop/known.php tips & tricks]
and an informative [http://www.lesswatts.org/projects/powertop/faq.php faq].

Alternatively (or complementary) to PowerTOP, running <code>strace -p $(pidof yourapp)</code>
for all your favorite or background running applications while they are expected to be
idle, will show the misbehaviors.

Beside CPU wakeups, disks spins are also power hungry. To detect what make your disk spinning,

<code>
sysctl vm.block_dump=1
</code>

will list all applications causing disks wakeups on the kernel's dmesg.
Other useful tools for this purpose are blktrace, iostat and lm-profiler
(from laptop-mode-tools suite).

See also [[#Misbehaving Userland]].

==BIOS settings==
Some Thinkpad BIOS (like 2.08 BIOS on {{X40}}) offer two very lame options,
with a very misleading online help (saying "Usually not needed"). That's

<code>
CPU power management: (default disabled)
PCI bus power management: (default disabled)
</code>

You should indeed ''enable'' them, else the deepest C3 and C4 ACPI C-states
are disabled.

==CPU==
Look at:
* [[How to make use of Dynamic Frequency Scaling]]
* [[Pentium M undervolting and underclocking]]

A good thing to keep in mind is that every CPU wakeup, even if it's for
a trivial light job, reduce the time the CPU stays on a deep power
saving C-state (like C3 or C4). Therefore you should ensure your applications
stay really idle when they meant to be idle (track shorts select timeouts
in loop, etc. with [[PowerTOP]]).

Also note that manually locking the CPU in the lowest P-state (frequency)
available is '''not''' an efficient way to improve battery lifetime. This will
cause the CPU to stay longer in C0 (power hungry C-state) doing hard work when
there is something to do, while it could have done this work faster by augmenting
the CPU freq, and returned back faster to a deeper, economic, C-state and to a
lower frequency (P-state).
The best is to let the kernel select the appropriates CPU frequencies by itself
with the help of in kernel CPU governors.
Have a look at [http://www.bughost.org/pipermail/power/2007-May/000166.html this explanation]
from Intel's kernel developer Arjan van de Ven.

==Kernel settings and patches==

===General settings===
The 2.6.21 kernel brought some very effective changes (like [[dynticks]]).
Later, 2.6.24-rc2 brought a lot of other power efficiency improvements.
If it's not already on your distribution and you value power efficiency,
you may think about compiling a recent kernel yourself.

Here are a few options (beside the ACPI and APM related one) that matter to
reduce power consumption or to help diagnosing consumers:

<code>
# From PowerTOP's FAQ:
CONFIG_NO_HZ
CONFIG_HIGH_RES_TIMERS
CONFIG_HPET
CONFIG_HPET_TIMER
CONFIG_CPU_FREQ_GOV_ONDEMAND
CONFIG_USB_SUSPEND
CONFIG_SND_AC97_POWER_SAVE
CONFIG_SND_HDA_POWER_SAVE
CONFIG_SND_HDA_POWER_SAVE_DEFAULT=3
CONFIG_TIMER_STATS
CONFIG_ACPI_BATTERY
CONFIG_CPU_FREQ_STAT
CONFIG_INOTIFY

# Not from the PowerTOP FAQ:
CONFIG_BLK_DEV_IO_TRACE
CONFIG_X86_ACPI_CPUFREQ
CONFIG_X86_SPEEDSTEP_CENTRINO depreciated as of kernel 2.6.24, use CONFIG_X86_ACPI_CPUFREQ
CONFIG_X86_SPEEDSTEP_ICH
CONFIG_X86_SPEEDSTEP_SMI
CONFIG_CPU_IDLE
CONFIG_CPU_IDLE_GOV_LADDER
CONFIG_CPU_IDLE_GOV_MENU
</code>

Those options are already in Fedora Core 7 and Ubuntu Gutsy (not Feisty) default i686 kernels.
PowerTOP FAQ also suggest to '''disable'''
CONFIG_IRQBALANCE and CONFIG_ACPI_DEBUG.

Also, you need to properly set APM and ACPI. Look at:
* [[Power Management]]
* [[How to make use of Power Management features]]

=== Kernel boot and module loading options ===
If you have an Intel chipset > ICH3 (cf. lspci output), as in most modern Thinkpads, you should
be using the integrated HPET timer (saves about 30 CPU wake ups per second). To see if
hpet is enabled on your laptop :

<code>
grep hpet /proc/timer_list
</code>

If this does not display "Clock Event Device: hpet", then add

<code>
hpet=force
</code>

to your kernel boot options (usualy in /boot/grub/menu.lst or lilo.conf).
Note that "hpet=force" is only available by default in 2.6.24-rc2 and above
(or as a separated patch for 2.6.22 and 2.6.23, see below).

===Useful Patches===

Thomas Gleixner High Resolution Timers (hrt) patchset brings many improvements,
like the cpuidle work and Udo A. Steinberg and Venki Pallipadi "force
enable HPET" patches (non HPET timers causes about 20-40 CPU wakeups/second, but
HPET is often hidden by the BIOS due to Windows XP deficiencies). Those are
fully merged in 2.6.24-rc1 vanilla kernel.
See http://www.tglx.de/projects/hrtimers/

Kristen Carlson Accardi from Intel has a patchset to turn on "Aggressive
Link Power Management" (ALPM) for the AHCI driver (for SATA bus). Also from
Accardi, SATA Asynchronous Notification (SATA AN), alows SATA link to notify
media insertions (thus avoid hal polling the cdrom). Those patches were merged
in 2.6.24-rc2 kernel (AN needs also support in hal to be used).
See: http://www.kernel.org/pub/linux/kernel/people/kristen/patches/SATA/alpm/

As of now (2.6.24-rc8), the linux kernel doesn't support PCI Express power
management (aka PCIe ASPM, aka PCIe LPM). Shaohua Li from Intel submited a
patch on LKML (http://lkml.org/lkml/2008/1/17/544 ) though, and reported it
to reduce power consumption by 1.3 watts for a system with three PCIe links.

The [[HDAPS]] disk protection systems can reduce battery life.
Matthew Garrett provides [http://www.linuxpowertop.org/patches/hdaps.patch a patch]
that prevents hdaps kernel module to generate interrupts when
this feature isn't used.

===Useful sysctls===
The meaning of those settings is explained case by case on the relevant
sections of this document. But for convenience sake, we group them here too.

Note that the "ondemand" scaling governor is recommended by Intel developers
for energy efficiency: it's expected to be more efficient than the "powersave"
governor, or than userspace daemons (like cpufreq-utils, cpufreqd, powernowd...).
Look [http://www.bughost.org/pipermail/power/2007-May/000071.html here],
[http://www.bughost.org/pipermail/power/2007-May/000073.html here], or
[http://www.bughost.org/pipermail/power/2007-May/000166.html here] for a
kernel developer explanation about "ondemand" being better on modern Intel CPUs.

The "link_power_management_policy" tunable won't be available unless you
run a 2.6.24-rc2 or more kernel, or applied Kirsten patchset, have an Intel
AHCI compatible chipset, and use SATA drives.

<code>
echo 5 > /proc/sys/vm/laptop_mode
echo 0 > /proc/sys/kernel/nmi_watchdog
echo Y > /sys/module/snd_ac97_codec/parameters/power_save
echo 1 > /sys/devices/system/cpu/sched_mc_power_savings
echo ondemand > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
echo 1500 > /proc/sys/vm/dirty_writeback_centisecs
for i in /sys/bus/usb/devices/*/power/autosuspend; do echo 1 > $i; done
# those sysctl's are only available if you have an AHCI compatible SATA
# controler and use kernel > 2.6.24-rc2 (or use Kristen ALPM patchset) :
echo min_power > /sys/class/scsi_host/host0/link_power_management_policy
echo min_power > /sys/class/scsi_host/host1/link_power_management_policy
</code>

If you're running a kernel older than 2.6.22 do this. Not needed for kernels 2.6.22 onward:

<code>
cd /sys/devices/system/cpu/cpu0/cpufreq
cat ondemand/sampling_rate_max > ondemand/sampling_rate
</code>

==ATA drives==
Hard drives and CDRom drives spinning is very costly. To improve battery
lifetime, you should reduce disks access (or devices polling) the more you
can.

===Hard Drives===

The files access time update, while mandated by POSIX, is causing lots of
disks access; even accessing files on disk cache may wake the ATA or USB
bus. If you don't use this feature, disable it via:

<code>
mount -o remount,relatime / # and so on for all mounted fs
</code>

(On older kernels you may need to use <tt>noatime</tt> instead of <tt>relatime</tt>.)

Also consider merely using a larger value for
commit=nrsec
Sync all data and metadata every nrsec seconds. The default value is 5 seconds.
See man mount(8).

Use laptop_mode to reduce disk usage by delaying and grouping writes. You should enable
it, at least while on battery. See [[Laptop-mode]] for more details:

<code>
echo 5 > /proc/sys/vm/laptop_mode
</code>

The default kernel dirty page writeback frequency is very conservative. On
a laptop running on battery, one might find more appropriate to reduce it:

<code>
echo 1500 > /proc/sys/vm/dirty_writeback_centisecs
</code>

Some power saving hard drives features can be activated with hdparm (beware
that "-B 1" may reduce your drive lifetime, if you have lot of intermittent
disk activity causing lots of heads load/unloads: so reduce I/O activity first,
as explained above, in order to get longer disks idling periods).
For more details look at [[How to make use of Power Management features]] :

<code>
hdparm -B 1 -S 12 /dev/sda # and/or any other disk device
</code>

====SATA Link Power Management====
On kernels 2.6.24 and new this enables SATA Link Power Management:
<code>
echo min_power > /sys/class/scsi_host/host0/link_power_management_policy
echo min_power > /sys/class/scsi_host/host1/link_power_management_policy
</code>

Disable it by replacing <code>min_power</code> with <code>max_performance</code>.

On Hardy Heron with a 2.6.24-16 kernel, a suspend/resume cycle is much quicker if you disable SATA Link Power Management before initiating the suspend. As of Intrepid Ibex and kernel 2.6.27, this should be fixed. ([https://bugs.launchpad.net/linux/+bug/234047 Launchpad bug 234047], [http://bugzilla.kernel.org/show_bug.cgi?id=10817 Kernel bug 10817])

====Laptop Mode Tools====

The [http://samwel.tk/laptop_mode/ Laptop Mode Tools] utility implements many of the above power-saving measures from disks, and some others.

===Optical drive===
The optical drive is reported to consume power even when not accessed. See

* [[How to hotswap UltraBay devices|Eject the UltraBay optical drive]], or just turn off its power supply (i.e., run the appropriate eject script but leave the drive inserted).
* [[How to set optical drive speed|Reduce the spinning speed of the optical drive]].

The hald daemon polling tends to maintain the ATA buses out of power saving
modes, and to wakeup CDROM drive (except if you have a kernel >= 2.6.24, hal >= 0.5.10,
and SATA AN compatible devices). If you have a recent hald version, you
can stop this polling when on battery:

<code>
hal-disable-polling --device /dev/scd0 # or whatever your CD drive is
</code>

start polling again when on ac:
<code>
hal-disable-polling --enable-polling --device /dev/scd0 # or whatever your CD drive is
</code>

If your hald is not recent enough, consider suspending it when running on battery. Some moderns SATA buses and drivers supports a notification mechanism (SATA AN - Asynchronous Events Notifications) that obsolete the need for polling on modern hardware; support for this feature had been merged in Linux 2.6.24-rc1 and HAL 0.5.10.

==LCD Backlight/Brightness==
The LCD backlight is one of the very major power drain.
Reducing brightness to the lowest readable
level will save a lot of battery lifetime. Also, don't forget to configure
your screen saver to shutdown the screen backlight (rather than displaying some
eye candy), when no activity for a few minutes.

You can also let the system [[automatically reduce brightness]] after a
period of inactivity.

If you're choosing your Thinkpad laptop model, keep in mind that the screen
size affect the battery time greatly: more power needed for larger screens.

The very recent, but xorg standard way to control backlight from CLI is
using xbacklight. ie. to set backlight at half the brightness:

<code>
xbacklight -set 50
</code>

You should configure the DPMS to shutdown the screen when idle (rather than
displaying a fancy but power consuming screensaver). ie. to turn off the
display after 5mn of idling:

<code>
xset +dpms
xset dpms 0 0 300
</code>

==Graphic controllers==
All xorg Thinkpad graphics chipsets drivers (ati, radeon, fglrx, i810) have
the same bug causing very frequent CPU wakeups when DRI is activated, even
when you don't use any 3D application.
This problem is partly fixed on xorg git tree but not released as of xorg
7.2. If you value more battery than 3D, you should disable DRI: put this on
the /etc/X11/xorg.conf "Device" of you graphic controller:

<code>
Option "NoDRI"
</code>

Also be sure that DPMS is working: <code>grep DPMS /var/log/Xorg.0.log</code>
should output "DPMS enabled". If not, put <code>Option "DPMS"</code> in your config.
See the section above about how to enable dpms driven display power saving.

On recent xrandr/xorg versions, you can disable the TV output (or any other detected
as connected but not used outputs) when you're not using it: it's known to consume power.

<code>
xrandr # see all displays listed here, but that you don't actually use and disable them.
xrandr --output TV --off # for instance (if "xrandr" above listed a connected output named "TV" that you don't use)
</code>

When you don't have an external monitor plugged, disable CRT and DVI output
(for some, this can make a difference in power usage) :
<code>
echo crt_disable > /proc/acpi/ibm/video
echo dvi_disable > /proc/acpi/ibm/video
</code>

Some drivers have specials power saving mode, and/or allows underclocking the GPU. See also:
* [[How to make use of Graphics Chips Power Management features]], or with [[Rovclock]] on ATI.
* [[Problem with high power drain in ACPI sleep]]

==USB Subsystem==
The kernel support an efficient USB 2.0 power saving feature if you enabled
CONFIG_USB_SUSPEND. This may not trigger in when you have an USB device
plugged (and beside, USB devices tends to suck power on their own), so avoid
using such devices when on battery. To enable it by default, you must add the line
<code>
options usbcore autosuspend=1
</code>
to your <tt>/etc/modprobe.conf</tt> or add it to (and create if necessary) the file <tt>/etc/modprobe.d/usbcore</tt> depending on how your distribution organises modprobe configuratoin.

If on the other hand, you have <tt>usbcore</tt> built into your kernel, you can add this in the kernel boot options (ie. in grub's menu.lst):

<code>
usbcore.autosuspend=1
</code>

or at runtime, per device, with:

<code>
for i in /sys/bus/usb/devices/%s/power/autosuspend; do echo 1 > $i; done
</code>

USB 1.1 is worst. It needs polling the bus frequently, hence can't really go
in a low power mode when you enabled it, even if you don't have any device
plugged. You'd better remove it when you don't use a 1.1 device:

<code>
rmmod uhci_hcd
</code>

If you don't intend to use any device needing USB 1.1 (unfortunately, the built-in bluetooth and fingerprint-reader are USB 1.1 devices), the USB 1.1 support can also be totally avoided. On Debian and derivatives, just do:

<code>
echo "blacklist uhci_hcd" >> /etc/modprobe.d/blacklist
</code>

==PCMCIA/CardBus==
Same for PCMCIA/CardBus. Some users experiences interrupts clouds (sometime up to
several thousands interrupts/second) causing CPU wakeups, thus totally preventing
the CPU to reach lower C-states.
If you don't use PCMCIA, you may disable it the same way (unloading seems insufficient
to restore the system properly, you have to boot without it):

<code>
echo "blacklist pcmcia" >> /etc/modprobe.d/blacklist
echo "blacklist yenta_socket" >> /etc/modprobe.d/blacklist
</code>

==Sound==
ALSA has a power saving feature that should be enabled on your kernel
(CONFIG_SND_AC97_POWER_SAVE). Note that this low power mode won't trigger in
unless you muted all sound inputs (micro, line in etc.). This feature has
to be activated with:

<code>
amixer set Line mute nocap
amixer set Mic mute nocap
echo Y > /sys/module/snd_ac97_codec/parameters/power_save
</code>

More radical: you can unload all sound related modules when you are on
battery, or mute the sound system (echo mute > /proc/acpi/ibm/volume).

See also [[How to enable audio codec power saving]].

==Wireless Interface==
===intel wireless===
Wireless network consume a lot of power.
To save power, you can kill the Wi-Fi radio when it's not in use:

<code>
echo 1 > /sys/bus/pci/devices/*/rf_kill
</code>

If you need Wi-Fi, you can also reduce power consumption (at the price of
performances) by activating the power saving modes:

<code>
iwpriv eth1 set_power 5
</code>

For drivers using the new Wi-Fi kernel framework (mac80211/cfg80211),
the canonical way to do this is now:

<code>
for i in /sys/bus/pci/devices/*/power_level ; do echo 5 > $i ; done
</code>

Most drivers, like ipw2200, that don't use the new mac80211 framework place the
interfaces in aggressive scanning mode when they are not associated with any
Access Point, even when the interface is down (more info about this on Intel's
[http://www.lesswatts.org/tips/wireless.php LessWatts] website).
This behavior consumes a lot of power, even more than when the interface
is plain active and in use. But this can disabled at module's load time :

<code>
rmmod ipw2200
modprobe ipw2200 associate=0
</code>

You can fix this setting by placing the following in /etc/modprobe.d/options
(Debian/Ubuntu) or in /etc/modprobe.conf (Red Hat/Fedora):

<code>
options ipw2200 associate=0
</code>

Reducing beacon intervals on your Access Point to 1 per second will also
reduce network card interrupts, therefore power savings. This shouldn't have
negatives side effects.

See also, to activate power saving on the wireless network card:
* For [[Intel PRO/Wireless 2200BG Mini-PCI Adapter]] and [[Intel PRO/Wireless 2915ABG Mini-PCI Adapter]], see instructions for the [[ipw2200]] driver.
* For [[Intel PRO/Wireless 3945ABG Mini-PCI Express Adapter]], see the [http://ipw3945.sourceforge.net/README.ipw3945 ipw3945 driver README]

==Ethernet Controler==
If you don't use Wake-on-LAN, you should disable it for your network card,
because it sucks a lot of power:

<code>
ethtool -s eth0 wol d
</code>

If you can, try to reduce useless network activity on your ethernet
segment, coming to your NIC (ie. uneeded broadcasts), those cause
interrupts and CPU wakeups.

Forcing 100Mbps full-duplex speed on a gigabit ethernet NIC can also save a lot of power (~1W) on most network workloads. This also reduces components temperature (e.g., [[Thermal Sensors|thermal sensor]] 0xC0 on the {{T43}} cools down by 5 degree between 1000Mbps and 100Mbps, and another 1 degree for 10Mbps).

<code>
ethtool -s eth0 autoneg off speed 100
</code>

Note, however, that if the network device on the other side has auto-negotiation enabled (which is very common) and you turn auto-negotiation off, the other side will assume half-duplex mode and you will experience a significant loss of performance.

==Bluetooth==
When you don't need bluetooth, disable it. Because of its radio,
bluetooth is not power friendly.

<code>
hciconfig hci0 down ; rmmod hci_usb
echo disable > /proc/acpi/ibm/bluetooth
</code>

==Modem==
When was the last time you used your analog modem? If you can't remember, you probably just don't need it. If it is on a separate module in your laptop, simply remove it. Store it in a ESD safe place (like the bag in which your last addon card or hard drive was packed), in case you should need it again. This won't save you a lot of power and weight, but why carry something around you never use.

==System Fans==
Fans consumes power when running, so you may look at the [[ACPI fan control script]].

==Misbehaving Userland==
You should avoid using Beagle, Compiz, Beryl, XMMS, gnome-power-manager
and Evolution while on battery.
Look at the PowerTOP's [http://www.linuxpowertop.org/known.php known problems]
list.

Deactivate desktop animations (blinking cursor on the terms, animated wallpapers, ...): they cause regular X (therefore kernel and CPU) wakeups.

In short, while on battery, you should stop all applications that don't really stay idle when you're not using them. This means applications that:
* Wakes up the CPU too often (by polling something, because of too short select() timeouts, ...)
* Access the disks at regular intervals
* Access an hardware bus (USB, ATA, ...) at regular intervals
To find those offenders run:
* <code>strace -p $(pidof yourapp)</code> # for all your running applications
* <code>powertop</code>
* <code>sysctl vm.block_dump=1</code> # and look at dmesg
* <code>ps aux | awk '{print$10,$11}' | sort -n</code> # will list all running softs sorted by used cpu time
Please, don't forget to fill a bug when you find such a misbehaving software.
{{NOTE|Not all software is evil, buggy or badly written. Some produce regular activity because they have to, in order to provide their intented functionality. Think twice before filling bugs about this.}}

==See Also==
* [[How to measure power consumption]]
* [[Script for monitoring power consumption]]
* Battery [[maintenance]]

==External resources==
* [http://www.free-it.de/archiv/talks_2005/paper-11017/paper-11017.html ''Current trends in Linux Kernel Power Management''], Dominik Brodowski, 2005
* [http://www.linuxpowertop.org PowerTOP] website
* [http://www.gentoo.org/doc/en/power-management-guide.xml Power Management Guide] from the Gentoo Linux documentation
* [http://mailman.linux-thinkpad.org/pipermail/linux-thinkpad/2005-November/030478.html When/where/what for low power consumption?] (thread on Linux-Thinkpad)
* Intel's [http://www.lesswatts.org/ LessWatts] "''Saving power on Linux''" website
* ''8 hours of battery life on your lap(top)'' ([http://atrey.karlin.mff.cuni.cz/~pavel/swsusp/8hours.odp ODP]/[http://atrey.karlin.mff.cuni.cz/~pavel/swsusp/8hours.pdf PDF]), a presentation by Pavel Machek

[[Category:600X]] [[Category:A20m]] [[Category:A20p]] [[Category:A21e]] [[Category:A21m]] [[Category:A21p]] [[Category:A22e]] [[Category:A22m]] [[Category:A22p]] [[Category:A30]] [[Category:A30p]] [[Category:A31]] [[Category:A31p]] [[Category:i1200]] [[Category:i1300]] [[Category:i1620]] [[Category:G40]] [[Category:G41]] [[Category:R30]] [[Category:R31]] [[Category:R32]] [[Category:R40]] [[Category:R40e]] [[Category:R50]] [[Category:R50e]] [[Category:R50p]] [[Category:R51]] [[Category:R52]] [[Category:R60]] [[Category:R60e]] [[Category:T20]] [[Category:T21]] [[Category:T22]] [[Category:T23]] [[Category:T30]] [[Category:T40]] [[Category:T40p]] [[Category:T41]] [[Category:T41p]] [[Category:T42]] [[Category:T42p]] [[Category:T43]] [[Category:T43p]] [[Category:T60]] [[Category:T60p]] [[Category:T61]] [[Category:X20]] [[Category:X21]] [[Category:X22]] [[Category:X23]] [[Category:X24]] [[Category:X30]] [[Category:X31]] [[Category:X32]] [[Category:X40]] [[Category:X41]] [[Category:X41 Tablet]] [[Category:X60]] [[Category:X60s]] [[Category:X61]] [[Category:X61s]] [[Category:Z60m]] [[Category:Z60t]] [[Category:Z61t]] [[Category:Z61e]] [[Category:TransNote]]

Problem with high pitch noises

2008-12-06T13:31:25Z

Telofy: /* Disable USB */

Information on strange high pitch, low volume noises emitted by ThinkPads.

==Problem description==
Even though ThinkPads are known as very silent notebooks, they tend to emit different, mostly high pitch noises in certain circumstances. The noises are of low volume and hence not realized by everyone or at least tolerated by most people. However, there are those with "bat like ears" that hear them and might be annoyed by that.

==Affected Models==
Noises have been experienced in the following situations:
{| border="1" cellspacing="0" cellpadding="2"
|-
! style="vertical-align:top;background-color:#DDDDDD;" | situation
! style="vertical-align:top;background-color:#DDDDDD;" | noise description
! style="vertical-align:top;background-color:#DDDDDD;" | affected models
|-
| style="vertical-align:top;" |
Plugged into AC / running at high CPU frequency
| style="vertical-align:top;" |
soft crackling, buzzing noise
| style="vertical-align:top;" |
*{{T41}}
**2379-DJU
|-
| style="vertical-align:top;" |
ThinkPad suspended to RAM
| style="vertical-align:top;" |
constant high pitch noise
| style="vertical-align:top;" |
*{{T42p}}
|-
| style="vertical-align:top;" |
ThinkPad connected to power and switched off, with battery fully charged
| style="vertical-align:top;" |
constant high pitch noise
| style="vertical-align:top;" |
*{{T41p}}
**2373-GHG
|-
| style="vertical-align:top;" |
moving windows or just the mouse in xorg
| style="vertical-align:top;" |
strange noise like a rapid series of very short high pitch noises adding to a constant kind of whistling (only as long as the movement goes)
| style="vertical-align:top;" |
*{{A21m}}
**2628
*{{T41p}}
**2373-GHG
*{{T60}}
|-
| style="vertical-align:top;" |
Thinkpad connected to power or working on battery, also when suspended to RAM
| style="vertical-align:top;" |
High pitch noise also when HD is powered down.
| style="vertical-align:top;" |
*{{T23}}
**2647-DG4
*{{X24}}
**2662-MWG
|-
| style="vertical-align:top;" |
Thinkpad connected to power battery charged less than 60%
| style="vertical-align:top;" |
High pitch noise till battery is charged more than 60%.
| style="vertical-align:top;" |
*{{T41p}}
**2373-GEG
|-
| style="vertical-align:top;" |
Constantly, if AC connected
| style="vertical-align:top;" |
High pitched, low volume constant noise.
| style="vertical-align:top;" |
*{{T40}}
**2373-88U
|-
| style="vertical-align:top;" |
When the CPU freq jumps up to 1Ghz or above, or when the laptop is in suspend mode
| style="vertical-align:top;" |
Constant high pitched
| style="vertical-align:top;" |
*{{R50}}
**1829-6DM
|-
| style="vertical-align:top;" |
(May come from harddisk.)
| style="vertical-align:top;" |
continuous, intermittent, low volume, high pitched
| style="vertical-align:top;" |
*{{600X}}
|-
| style="vertical-align:top;" |
ACPI puts the processor into the C3 or C4 power saving states (i.e., the system is idle).
| style="vertical-align:top;" |
High-pitched crackling noise.
| style="vertical-align:top;" |
*{{X41}}
*{{T43}}
**2686-DGU
*{{T43p}}
*{{T60}}
**2007-72U
*{{T21}}
*{{T20}}
**2648-46U
|-
| style="vertical-align:top;" |
Cpufreqd (or powernowd etc.) slows down the processor, for exemple at the end of an heavy task.
| style="vertical-align:top;" |
High-pitched crackling noise.
| style="vertical-align:top;" |
*{{T42}}
|-
| style="vertical-align:top;" |
When on battery
| style="vertical-align:top;" |
Noise level varies from inaudible to clearly audible, screeching sound, or sometimes beeping (when wifi is on).
| style="vertical-align:top;" |
*{{A21m}}
**2628
*{{R51}}
**EHG-1829
*{{R52}}
**1858-A11
**1846-B5G
*{{R60}}
**9461-DXG
**9462-77G
**9456-HTG
**9461-DXG
*{{R60e}}
**0657-A9G
**0657-3LG
*{{T43}}
**2686-DGU
**1871-4AG
*{{T60}}
**2007-72U
**1951-24G
**1951-24G
**2007-49G
**2007-FUG
*{{T60p}}
**2007-FBG
*{{T61}}
**7659-12G
**8898-5FG
**6463-9WG
*{{x60}}
*{{x31}}
**2673-CBU
*{{Z61m}}
**9450-3HG
**9452-128
**9452-W5Q
*{{Z61t}}
**9440-2QU

|-
| CPU is used much AND laptop is on AC power AND the TFT panel is enabled.
| Screetching high pitch noise, like a million crickets
|
* {{X41}}

|-
| Network is pluged in and networkload is ~100%.
| low volume highfreq. pitch noise from left speaker or cpu.
|
*{{Z60m}}, {{Z60t}}
*{{T40}}
*{{T43}}
**2687-DDU

|-
| Constant, but is louder when Tablet Pen is near screen, on battery power
| high pitch noise, screeching sounds *solved by "Media player paused" (see below) and also by BIOS versions 1.05 and later.
|
*{{X60_Tablet}}
**6366-4DU
|}

==Affected Operating Systems==
All, though Linux appears especially susceptible.

==Possible sources==

* '''CPU activity:''' On some models the noise is triggered by certain CPU power states or activity patterns (as proven [http://www.wisdom.weizmann.ac.il/~tromer/acoustic here]).
* '''Graphics processor:''' In some models from the T2x era, e.g. the {{T23}}, the problem was related to the graphics circuitry and occured especially or only while making use of DirectDraw functions. IBM was able to fix it through a BIOS upgrade.
* '''Hard disk:''' On some ThinkPads the processor and hard disk are adjacent and produce similar noise. For example, in the {{X41}} the sound generated by the hard disk is likely to be loudest at the vent.
* '''Gigabit Ethernet processor:''' In some models (e.g., {{T43}}) high ethernet activity causes a high pitch noise.

* '''Screen brightness:''' on an {{X31}}, a hissing sound is started whenever screen brightness is not full.

==Status==

The problem is highly specific to operating system, model and even individual machines. There is no universal solution, but on most machines one of the following will reduce or eliminate the noise (possibly at some cost in power consumption).

==Solutions for CPU-triggered noise==

===Limit ACPI CPU power states===

By default, the kernel supports up to eight ACPI CPU power saving states (C-states), called C1 through C8 (but the ThinkPad BIOS and hardware often offers (or remaps them to) only C1 to C4). Often only the extreme power saving modes C4 or C3 produce the noise, so the noise can be stopped by instructing the Linux ACPI code to use only lower modes. This has a cost, though: disabling C3 and C4 will make the CPU consume more power and reduce battery life.

To forbid the ACPI driver from using C4 (this fixed the problem with on some ThinkPad {{T43}}, {{T43p}} and {{T41}}):
* If the ACPI processor component is compiled as built-in (<tt>CONFIG_ACPI_PROCESSOR=y</tt>):
**Pass the {{bootparm|max_cstate|3}} kernel argument.
* If the ACPI processor component is loaded as a module (<tt>CONFIG_ACPI_PROCESSOR=m</tt> and <tt>processor</tt> shows in the output of {{cmdroot|lsmod}}), do either of:
** Pass the {{bootparm|processor.max_cstate|3}} kernel argument (this does not work in Ubuntu 5.10 with default kernel).
** Add <code>options processor max_cstate=3</code> to {{path|/etc/modprobe.conf}} (or {{path|/etc/modprobe.conf.local}}, or {{path|/etc/modprobe.d/...}}, depending on your system) (this does not work in Ubuntu 5.10 with default kernel).
** {{cmdroot|echo 3 > /sys/module/processor/parameters/max_cstate}} (this can be changed in runtime for experimentation). (If may need to be set again upon resume from suspend, e.g., in the wakeup script.)
** (On Ubuntu 5.10, the default kernel uses <code>processor</code> as a module. Unfortunately, the script loading it, {{path|/etc/init.d/acpid}}, ignores the <code>options processor max_cstate=3</code> setting in {{path|/etc/modprobe.d/<my file>}}. As a solution for this specific problem, add the line <code>echo 2 > /sys/module/processor/parameters/max_cstate</code> directly to {{path|/etc/init.d/acpid}}, at the end of the function <code>load_modules()</code>, immediately after the line <code>echo "$PRINTK" > /proc/sys/kernel/printk</code>.)
** On Gentoo: Configure your Thinkpad as described in the [http://www.gentoo.org/doc/en/power-management-guide.xml Power Management Guide]. Then as root create the files {{path|/etc/init.d/limit-sleep-states}} and {{path|/etc/conf.d/limit-sleep-states}} as below. After that just issue the command {{cmdroot|rc-update add limit-sleep-states default}} to limit the sleep states only when running on AC power, or {{cmdroot|rc-update add limit-sleep-states default battery}} to always limit the sleep states.
cat <<EOF > /etc/init.d/limit-sleep-states
#!/sbin/runscript

depend() {
need acpid
}

start() {
ebegin "Limiting CPU sleep state to C${LIMIT_CSTATE}"
echo $LIMIT_CSTATE > /sys/module/processor/parameters/max_cstate
eend $?
}

stop() {
ebegin "Removing CPU sleep state limit"
echo $REMOVE_CSTATE > /sys/module/processor/parameters/max_cstate
eend $?
}
EOF

cat <<EOF > /etc/conf.d/limit-sleep-states
# limit CPU sleep state to the following value (adjust accordingly)
LIMIT_CSTATE=3
# some value which is higher than all available sleep states
REMOVE_CSTATE=8
EOF

To also forbid the C3 state, replace "<tt>3</tt>" with "<tt>2</tt>" above (this fixed the problem on some ThinkPad {{X40}}, {{X41}}, {{X60}}, {{T60}}, {{T61}}, {{Z61t}} and {{R52}}, as well as on {{T20}} where C4 is not supported at all).

Note that these options affect power consumption when the CPU is idle. For example, here is the [[How to measure power consumption|measured power consumption]] on a ThinkPad {{T43}}:
* {{bootparm|processor.max_cstate|4}}: 15160mW (default, noisy)
* {{bootparm|processor.max_cstate|3}}: 15770mW (660mW higher, silent)
* {{bootparm|processor.max_cstate|2}}: 16100mW (2940mW higher, silent)

One can control how often Linux tries to enter the C3 state by using the {{bootparm|processor.bm_history|<bitmask>}} parameter on kernels with a scheduler frequency below 800Hz (and if you have noise problems, you really should not be running the kernel at 1000Hz...). Setting {{bootparm|processor.bm_history|0xFFFFFFFF}} will cause C3 to be entered less often. This will waste more power as the CPU won't do C3 or C4 as often, but at least it doesn't forbid C3 and C4 permanently, unlike {{bootparm|max_cstate|2}}.

See the [http://thinkwiki.org/wiki?title=Talk:Problem_with_high_pitch_noises discussion page] for further information and success reports.

*Jakob Schou Pedersen: Editing the file {{path|/etc/init.d/acpid}} as described above (the last solution) worked on my T43 :-)

===Turn off CPU power saving in the BIOS===

Go into the BIOS and turn off the power saving processor feature that puts it into idle mode. This should be somewhere under Config/Power - look for "CPU Power Management", the default being automatic. Set "CPU Power Management" to "Disabled" (This worked on a ThinkPad {{T43}}, {{T21}}, {{X60s}}, {{T60}} and {{Z61m}}). However, this also affects power consumption when the CPU is idle, it's similar to disabling the C4/C3 ACPI CPU power state. For example, on a Z61m 9450-3HG, a full charged battery with power management enabled in the BIOS provides the notebook with power for about 3.5h, if disabled, the battery-lifetime is only about 2h.

===Disable ACPI CPU power states===

Completely disable CPU ACPI power states. Discussion:

*From Martin Steigerwald: I made the observation that I get at least less high pitch noises on my {{T23}} when I do not use the two ACPI modules "processor" and "thermal" (depends on the first one). I have no clue, why. Anyone with similar experiences?
:Omar Yasin: I've got a {{R52}} and when I load the same ACPIO modules the high pitch noises are not as loud but I can still hear them.
*Kaspar Schleiser: On my {{T23}} the noise is less loud when setting max_cstate to 2, but to completely silence it, I have to set it to "1". Is that the same as removing the "processor"-module? "cat /proc/acpi/battery/BAT0/state" does not show increased power drain.
*Niko Ehrenfeuchter: I'm experiencing the same here on my {{X24}}. Removing the "processor" module also stops the pitch noise, which does ONLY occur when setting the CPU to maximum speed (using cpufreq). On low speed it's completely silent, even having loaded the processor module.

*Rolf Adelsberger: I can confirm this: the high pitch noise is only remarkable (at least with my ears ;-) ) if the processor speed is set to maximum frequency.

*Stefan Baums: My {{X41}} produced a high-pitched crackle from the processor vent on the left. Changing HZ did nothing, and the 'processor' module could not easily be removed from the system (Ubuntu 5.04). What solved the problem for me was adding {{bootparm|idle|halt}} to the boot command line. Unfortunately, this solution only lasts until the first hibernation or suspend - when the computer ({{X41}}) resumes, the high-pitched crackle is back.

* The {{bootparm|idle|halt}} solution combined with setting <code>#define HZ 100</code> in the kernel fixes the problem on a {{T43}}.

* jhatch: {{bootparm|idle|halt}} plus <code>#define HZ 100</code> also worked on my {{T43}}. It still reverts back to noisy after a suspend/resume though. This needs to be fixed...

===Use both C-States (sleep modes) and P-States (frequency scaling)===
*Max Gaukler: I had the problem with a "beeping" noise of my {{R60}} on battery. When using powertop I recognised that it went into C3 (deep sleep mode), but it was always running at the highest possible frequency. I followed the instructions in [[How_to_make_use_of_Dynamic_Frequency_Scaling|How to make use of Dynamic Frequency Scaling]] and the noise disappeared except for a short time during boot until frequency scaling has been loaded.

===Change the timer interrupt frequency===

Change the "HZ" kernel constants to alter the frequency of timer interrupts. Discussion:

{{NOTE|The timer interrupt frequency (HZ) in current Linux kernels is directly tied to the kernel task scheduler. Lower frequencies provide larger time-slices and thus also higher latencies (which may kill latency-sensitive applications like audio processing). 100Hz ended up as the recommended "server" setting (because it increases disk/CPU throughput in a latency-insensitive environment). Higher frequencies are better for latency-sensitive applications, and improve desktop responsivity at the cost of less processor throughput. 1000Hz ended up as the recommended "desktop" setting.}}

*Andreas Karnahl: i've read in several forums it has something to do with the "idle"-state (or "C3") of the processor. There is a frequency called "timer interrupt" (or so mething like that). Since kernel 2.6x it is set to 1000 Hz by default (compared to 100 Hz in Kernel 2.4x). The exact reason i don't know, but it is safe to change this frequency to 100 Hz in kernel 2.6x (by the way, windows up to XP uses 100 Hz by default). Just do the following: 
: In {{path|[path to kernel-sources]/include/asm-i386/param.h}} find the line
:: <code>#define HZ 1000</code>
: and change the value of HZ to 100:
:: <code>#define HZ 100</code>
:Then recompile the kernel. After i changed it on my ThinkPad {{A30}} (under SuSE 9.2 and 9.3) and recompiling the kernel the high pitch noise is gone away.

* Omar Yasin: Worked on my {{R52}}, thanks.

* [[User:Thinker|Thinker]]: In modern kernels this constant is in the kernel configuration {{kernelconf|CONFIG_HZ|Processor type and features||Timer Frequency|||||}}.

* [[User:sklnd|sklnd]]: As of 2.6.21, enabling a tickless kernel (CONFIG_NO_HZ) seems to fix the sound issue on the X60. This also has the added benefit of causing the kernel to wake up less, which will improve battery life.

===Prevent idling===

Indirectly avoid power saving states by making sure the CPU is rarely idle:

* Paul RIVIER: Here is a really simple workaround. C3 / C4 states are mainly called when the cpu freq is higher than required, for example if your cpufreqd is lazy to slow down the frequency but quick to raise it. That is why I use powernowd with the builtin "passive" mode, which is lazy for raising frequency, but quick to go back to the lowest. Now I don't hear them as often as before, as I avoid C3/C4 states at high frequency.

* The problem also occurs on my {{X41}} with 2.6.11. Setting up [[How to make use of Dynamic Frequency Scaling|frequency scaling]] with the <code>ondemand</code> governor makes things a lot better, as the processor does not stay with the maximum frequency when in idle mode. It can be still heard sometimes, though.

* On a {{T43}} the noise was gone after dropping cpufreqd and switching to the ondemand governor - maybe because of the high sampling rate? (used the default: 10ms)

===Change the processor voltage===

Reducing the processor voltage (when possible) may decrease or eliminate the noise. On one ThinkPad {{T43}}, [[Pentium M undervolting and underclocking|undervolting the Pentium M processor]] eliminated the high-pitched noise. Compared to the other solutions this has the benefit of lower power consumption, both due to the undervolting itself and because there is no need to forbid high APCI CPU power saving modes.

===Kernel BIOS options===

Adding acpi_sleep=s3_bios and pci=bios as boot parameters significantly reduced the pitch noise on a T61. Seems to be the best solution so far, without losing battery capacity. If ondemand governor is enabled as well, the noise is almost gone.--[[User:Mozz|Mozz]] 13:14, 18 January 2008 (CET)

===Kernel Update===

The recent kernel update in Ubuntu 8.04 from 2.6.24-19 to 2.6.24-21 made the noise disappear on my T61. With the old kernel the sound was very audible when running on battery power, although setting the kernel BIOS options as specified in the paragraph above made it somewhat bearable. Now I can barely hear anything with the default startup options, even with my ear close to the laptop.

==Solutions for screen brightness related sounds==

===Disable BIOS brightness control===

The sound starts when on batteries as the BIOS automatically reduces screen brightness. To disable this, simply switch Config>Display>Brightness from
Normal to High. See also [[User:Piccobello/Hissing sound on battery|here]].

==Other solutions==

===Disable UltraBay===
*Naheed Vora: My {{T41}} (2373-268) started to give high pitch noise ocassionally, when I upgraded to 2.6.11 kernel. I tried to unload lot of modules but finally figured out that disabling bay stops the noise. If you have [[ibm-acpi]], do (need a cleaner solution): {{cmduser|echo eject >/proc/acpi/ibm/bay}} .

===Disable IrDA===
*Mike Perry: I was able to cure an intermittent high-pitched whine on both my {{X24}} and {{X40}} by disabling the Infrared port.

===Disable the Linuxant Modem Driver===
*Joern Heissler: I made another experience. I played around with linuxant conexant [[Modem Devices|modem]] drivers. After loading them I got some noise on my {{T42p}}.

===Media Player paused===
*Eilif Muller: On my {{R52}} the high-pitched noises go away if I load XMMS, play something then pause it.
*Jacob: On my {{T43}} DGU it goes away if I open mplayerc.exe and press play then pause it. This is the high-pitched noise that only shows up when I'm on battery.
*butcom: On my {{X60 Tablet}}, this tip works in Windows as well with Media Player Classic or Windows Media Player. Just open either program, start playing any music file and pause it and the screeching noise stops.

''I'd guess that the above tip works as when xmms or similar is running, it is uncompressing compressed audio/video, which is a processor intensive action. Keeping this paused means that the app won't 'let go' of the processor, forcing it to stay up and running, which stops it entering the higher powersave modes.''

===nice yes===

Run the command:
{{cmduser|nice yes > /dev/null}}.

This is a good way to test whether the processor is causing the interference, since it forces the CPU to stay at full power. Of course, this will make your system get warm, and probably turn on the fan, as well as eating power.

===Upgrade BIOS===
On a ThinkPad {{X60s}}, [[BIOS_Upgrade|upgrading the BIOS]] to version 1.06 eliminated the high pitch noise when running on battery.

On a ThinkPad {{R60}}, [[BIOS_Upgrade|upgrading the BIOS]] to version 2.19 eliminated the voice also.

===Disable USB===
On one {{T43}} and one {{X60}}, (partially) disabling USB using {{cmdroot|rmmod uhci_hcd}} significantly reduced the noise. Also, on a {{T60}} this trick worked well, doing ''rmmod/modprobe'' twice wiped the noise permanently.

This is likely a CPU-induced noise case, as disabling USB UHCI will reduce a lot the amount of busmaster activity while the computer is idle, and thus has a direct effect on the need for ACPI C-state transitions from C3/C4 to C2 or lower states in a {{T43}} or {{X60}}.

*syscrash: Plugging in my USB mouse has completely solved the problem for me.
*lorien: Plugging USB mouse helped me too {{T61}}
*telofy: Disabling USB "solved" the problem; so does disabling the CPU idle setting in the BIOS on my X200s.

===Suspend USB===
*Stefan Ott: On my X41, the noise seems to have stopped since I enabled "USB selective suspend/resume and wakeup" (CONFIG_USB_SUSPEND).
*babrodtk: This approach worked with an R60 as well.

Problem with high pitch noises

2008-12-06T13:29:20Z

Telofy:

Information on strange high pitch, low volume noises emitted by ThinkPads.

==Problem description==
Even though ThinkPads are known as very silent notebooks, they tend to emit different, mostly high pitch noises in certain circumstances. The noises are of low volume and hence not realized by everyone or at least tolerated by most people. However, there are those with "bat like ears" that hear them and might be annoyed by that.

==Affected Models==
Noises have been experienced in the following situations:
{| border="1" cellspacing="0" cellpadding="2"
|-
! style="vertical-align:top;background-color:#DDDDDD;" | situation
! style="vertical-align:top;background-color:#DDDDDD;" | noise description
! style="vertical-align:top;background-color:#DDDDDD;" | affected models
|-
| style="vertical-align:top;" |
Plugged into AC / running at high CPU frequency
| style="vertical-align:top;" |
soft crackling, buzzing noise
| style="vertical-align:top;" |
*{{T41}}
**2379-DJU
|-
| style="vertical-align:top;" |
ThinkPad suspended to RAM
| style="vertical-align:top;" |
constant high pitch noise
| style="vertical-align:top;" |
*{{T42p}}
|-
| style="vertical-align:top;" |
ThinkPad connected to power and switched off, with battery fully charged
| style="vertical-align:top;" |
constant high pitch noise
| style="vertical-align:top;" |
*{{T41p}}
**2373-GHG
|-
| style="vertical-align:top;" |
moving windows or just the mouse in xorg
| style="vertical-align:top;" |
strange noise like a rapid series of very short high pitch noises adding to a constant kind of whistling (only as long as the movement goes)
| style="vertical-align:top;" |
*{{A21m}}
**2628
*{{T41p}}
**2373-GHG
*{{T60}}
|-
| style="vertical-align:top;" |
Thinkpad connected to power or working on battery, also when suspended to RAM
| style="vertical-align:top;" |
High pitch noise also when HD is powered down.
| style="vertical-align:top;" |
*{{T23}}
**2647-DG4
*{{X24}}
**2662-MWG
|-
| style="vertical-align:top;" |
Thinkpad connected to power battery charged less than 60%
| style="vertical-align:top;" |
High pitch noise till battery is charged more than 60%.
| style="vertical-align:top;" |
*{{T41p}}
**2373-GEG
|-
| style="vertical-align:top;" |
Constantly, if AC connected
| style="vertical-align:top;" |
High pitched, low volume constant noise.
| style="vertical-align:top;" |
*{{T40}}
**2373-88U
|-
| style="vertical-align:top;" |
When the CPU freq jumps up to 1Ghz or above, or when the laptop is in suspend mode
| style="vertical-align:top;" |
Constant high pitched
| style="vertical-align:top;" |
*{{R50}}
**1829-6DM
|-
| style="vertical-align:top;" |
(May come from harddisk.)
| style="vertical-align:top;" |
continuous, intermittent, low volume, high pitched
| style="vertical-align:top;" |
*{{600X}}
|-
| style="vertical-align:top;" |
ACPI puts the processor into the C3 or C4 power saving states (i.e., the system is idle).
| style="vertical-align:top;" |
High-pitched crackling noise.
| style="vertical-align:top;" |
*{{X41}}
*{{T43}}
**2686-DGU
*{{T43p}}
*{{T60}}
**2007-72U
*{{T21}}
*{{T20}}
**2648-46U
|-
| style="vertical-align:top;" |
Cpufreqd (or powernowd etc.) slows down the processor, for exemple at the end of an heavy task.
| style="vertical-align:top;" |
High-pitched crackling noise.
| style="vertical-align:top;" |
*{{T42}}
|-
| style="vertical-align:top;" |
When on battery
| style="vertical-align:top;" |
Noise level varies from inaudible to clearly audible, screeching sound, or sometimes beeping (when wifi is on).
| style="vertical-align:top;" |
*{{A21m}}
**2628
*{{R51}}
**EHG-1829
*{{R52}}
**1858-A11
**1846-B5G
*{{R60}}
**9461-DXG
**9462-77G
**9456-HTG
**9461-DXG
*{{R60e}}
**0657-A9G
**0657-3LG
*{{T43}}
**2686-DGU
**1871-4AG
*{{T60}}
**2007-72U
**1951-24G
**1951-24G
**2007-49G
**2007-FUG
*{{T60p}}
**2007-FBG
*{{T61}}
**7659-12G
**8898-5FG
**6463-9WG
*{{x60}}
*{{x31}}
**2673-CBU
*{{Z61m}}
**9450-3HG
**9452-128
**9452-W5Q
*{{Z61t}}
**9440-2QU

|-
| CPU is used much AND laptop is on AC power AND the TFT panel is enabled.
| Screetching high pitch noise, like a million crickets
|
* {{X41}}

|-
| Network is pluged in and networkload is ~100%.
| low volume highfreq. pitch noise from left speaker or cpu.
|
*{{Z60m}}, {{Z60t}}
*{{T40}}
*{{T43}}
**2687-DDU

|-
| Constant, but is louder when Tablet Pen is near screen, on battery power
| high pitch noise, screeching sounds *solved by "Media player paused" (see below) and also by BIOS versions 1.05 and later.
|
*{{X60_Tablet}}
**6366-4DU
|}

==Affected Operating Systems==
All, though Linux appears especially susceptible.

==Possible sources==

* '''CPU activity:''' On some models the noise is triggered by certain CPU power states or activity patterns (as proven [http://www.wisdom.weizmann.ac.il/~tromer/acoustic here]).
* '''Graphics processor:''' In some models from the T2x era, e.g. the {{T23}}, the problem was related to the graphics circuitry and occured especially or only while making use of DirectDraw functions. IBM was able to fix it through a BIOS upgrade.
* '''Hard disk:''' On some ThinkPads the processor and hard disk are adjacent and produce similar noise. For example, in the {{X41}} the sound generated by the hard disk is likely to be loudest at the vent.
* '''Gigabit Ethernet processor:''' In some models (e.g., {{T43}}) high ethernet activity causes a high pitch noise.

* '''Screen brightness:''' on an {{X31}}, a hissing sound is started whenever screen brightness is not full.

==Status==

The problem is highly specific to operating system, model and even individual machines. There is no universal solution, but on most machines one of the following will reduce or eliminate the noise (possibly at some cost in power consumption).

==Solutions for CPU-triggered noise==

===Limit ACPI CPU power states===

By default, the kernel supports up to eight ACPI CPU power saving states (C-states), called C1 through C8 (but the ThinkPad BIOS and hardware often offers (or remaps them to) only C1 to C4). Often only the extreme power saving modes C4 or C3 produce the noise, so the noise can be stopped by instructing the Linux ACPI code to use only lower modes. This has a cost, though: disabling C3 and C4 will make the CPU consume more power and reduce battery life.

To forbid the ACPI driver from using C4 (this fixed the problem with on some ThinkPad {{T43}}, {{T43p}} and {{T41}}):
* If the ACPI processor component is compiled as built-in (<tt>CONFIG_ACPI_PROCESSOR=y</tt>):
**Pass the {{bootparm|max_cstate|3}} kernel argument.
* If the ACPI processor component is loaded as a module (<tt>CONFIG_ACPI_PROCESSOR=m</tt> and <tt>processor</tt> shows in the output of {{cmdroot|lsmod}}), do either of:
** Pass the {{bootparm|processor.max_cstate|3}} kernel argument (this does not work in Ubuntu 5.10 with default kernel).
** Add <code>options processor max_cstate=3</code> to {{path|/etc/modprobe.conf}} (or {{path|/etc/modprobe.conf.local}}, or {{path|/etc/modprobe.d/...}}, depending on your system) (this does not work in Ubuntu 5.10 with default kernel).
** {{cmdroot|echo 3 > /sys/module/processor/parameters/max_cstate}} (this can be changed in runtime for experimentation). (If may need to be set again upon resume from suspend, e.g., in the wakeup script.)
** (On Ubuntu 5.10, the default kernel uses <code>processor</code> as a module. Unfortunately, the script loading it, {{path|/etc/init.d/acpid}}, ignores the <code>options processor max_cstate=3</code> setting in {{path|/etc/modprobe.d/<my file>}}. As a solution for this specific problem, add the line <code>echo 2 > /sys/module/processor/parameters/max_cstate</code> directly to {{path|/etc/init.d/acpid}}, at the end of the function <code>load_modules()</code>, immediately after the line <code>echo "$PRINTK" > /proc/sys/kernel/printk</code>.)
** On Gentoo: Configure your Thinkpad as described in the [http://www.gentoo.org/doc/en/power-management-guide.xml Power Management Guide]. Then as root create the files {{path|/etc/init.d/limit-sleep-states}} and {{path|/etc/conf.d/limit-sleep-states}} as below. After that just issue the command {{cmdroot|rc-update add limit-sleep-states default}} to limit the sleep states only when running on AC power, or {{cmdroot|rc-update add limit-sleep-states default battery}} to always limit the sleep states.
cat <<EOF > /etc/init.d/limit-sleep-states
#!/sbin/runscript

depend() {
need acpid
}

start() {
ebegin "Limiting CPU sleep state to C${LIMIT_CSTATE}"
echo $LIMIT_CSTATE > /sys/module/processor/parameters/max_cstate
eend $?
}

stop() {
ebegin "Removing CPU sleep state limit"
echo $REMOVE_CSTATE > /sys/module/processor/parameters/max_cstate
eend $?
}
EOF

cat <<EOF > /etc/conf.d/limit-sleep-states
# limit CPU sleep state to the following value (adjust accordingly)
LIMIT_CSTATE=3
# some value which is higher than all available sleep states
REMOVE_CSTATE=8
EOF

To also forbid the C3 state, replace "<tt>3</tt>" with "<tt>2</tt>" above (this fixed the problem on some ThinkPad {{X40}}, {{X41}}, {{X60}}, {{T60}}, {{T61}}, {{Z61t}} and {{R52}}, as well as on {{T20}} where C4 is not supported at all).

Note that these options affect power consumption when the CPU is idle. For example, here is the [[How to measure power consumption|measured power consumption]] on a ThinkPad {{T43}}:
* {{bootparm|processor.max_cstate|4}}: 15160mW (default, noisy)
* {{bootparm|processor.max_cstate|3}}: 15770mW (660mW higher, silent)
* {{bootparm|processor.max_cstate|2}}: 16100mW (2940mW higher, silent)

One can control how often Linux tries to enter the C3 state by using the {{bootparm|processor.bm_history|<bitmask>}} parameter on kernels with a scheduler frequency below 800Hz (and if you have noise problems, you really should not be running the kernel at 1000Hz...). Setting {{bootparm|processor.bm_history|0xFFFFFFFF}} will cause C3 to be entered less often. This will waste more power as the CPU won't do C3 or C4 as often, but at least it doesn't forbid C3 and C4 permanently, unlike {{bootparm|max_cstate|2}}.

See the [http://thinkwiki.org/wiki?title=Talk:Problem_with_high_pitch_noises discussion page] for further information and success reports.

*Jakob Schou Pedersen: Editing the file {{path|/etc/init.d/acpid}} as described above (the last solution) worked on my T43 :-)

===Turn off CPU power saving in the BIOS===

Go into the BIOS and turn off the power saving processor feature that puts it into idle mode. This should be somewhere under Config/Power - look for "CPU Power Management", the default being automatic. Set "CPU Power Management" to "Disabled" (This worked on a ThinkPad {{T43}}, {{T21}}, {{X60s}}, {{T60}} and {{Z61m}}). However, this also affects power consumption when the CPU is idle, it's similar to disabling the C4/C3 ACPI CPU power state. For example, on a Z61m 9450-3HG, a full charged battery with power management enabled in the BIOS provides the notebook with power for about 3.5h, if disabled, the battery-lifetime is only about 2h.

===Disable ACPI CPU power states===

Completely disable CPU ACPI power states. Discussion:

*From Martin Steigerwald: I made the observation that I get at least less high pitch noises on my {{T23}} when I do not use the two ACPI modules "processor" and "thermal" (depends on the first one). I have no clue, why. Anyone with similar experiences?
:Omar Yasin: I've got a {{R52}} and when I load the same ACPIO modules the high pitch noises are not as loud but I can still hear them.
*Kaspar Schleiser: On my {{T23}} the noise is less loud when setting max_cstate to 2, but to completely silence it, I have to set it to "1". Is that the same as removing the "processor"-module? "cat /proc/acpi/battery/BAT0/state" does not show increased power drain.
*Niko Ehrenfeuchter: I'm experiencing the same here on my {{X24}}. Removing the "processor" module also stops the pitch noise, which does ONLY occur when setting the CPU to maximum speed (using cpufreq). On low speed it's completely silent, even having loaded the processor module.

*Rolf Adelsberger: I can confirm this: the high pitch noise is only remarkable (at least with my ears ;-) ) if the processor speed is set to maximum frequency.

*Stefan Baums: My {{X41}} produced a high-pitched crackle from the processor vent on the left. Changing HZ did nothing, and the 'processor' module could not easily be removed from the system (Ubuntu 5.04). What solved the problem for me was adding {{bootparm|idle|halt}} to the boot command line. Unfortunately, this solution only lasts until the first hibernation or suspend - when the computer ({{X41}}) resumes, the high-pitched crackle is back.

* The {{bootparm|idle|halt}} solution combined with setting <code>#define HZ 100</code> in the kernel fixes the problem on a {{T43}}.

* jhatch: {{bootparm|idle|halt}} plus <code>#define HZ 100</code> also worked on my {{T43}}. It still reverts back to noisy after a suspend/resume though. This needs to be fixed...

===Use both C-States (sleep modes) and P-States (frequency scaling)===
*Max Gaukler: I had the problem with a "beeping" noise of my {{R60}} on battery. When using powertop I recognised that it went into C3 (deep sleep mode), but it was always running at the highest possible frequency. I followed the instructions in [[How_to_make_use_of_Dynamic_Frequency_Scaling|How to make use of Dynamic Frequency Scaling]] and the noise disappeared except for a short time during boot until frequency scaling has been loaded.

===Change the timer interrupt frequency===

Change the "HZ" kernel constants to alter the frequency of timer interrupts. Discussion:

{{NOTE|The timer interrupt frequency (HZ) in current Linux kernels is directly tied to the kernel task scheduler. Lower frequencies provide larger time-slices and thus also higher latencies (which may kill latency-sensitive applications like audio processing). 100Hz ended up as the recommended "server" setting (because it increases disk/CPU throughput in a latency-insensitive environment). Higher frequencies are better for latency-sensitive applications, and improve desktop responsivity at the cost of less processor throughput. 1000Hz ended up as the recommended "desktop" setting.}}

*Andreas Karnahl: i've read in several forums it has something to do with the "idle"-state (or "C3") of the processor. There is a frequency called "timer interrupt" (or so mething like that). Since kernel 2.6x it is set to 1000 Hz by default (compared to 100 Hz in Kernel 2.4x). The exact reason i don't know, but it is safe to change this frequency to 100 Hz in kernel 2.6x (by the way, windows up to XP uses 100 Hz by default). Just do the following: 
: In {{path|[path to kernel-sources]/include/asm-i386/param.h}} find the line
:: <code>#define HZ 1000</code>
: and change the value of HZ to 100:
:: <code>#define HZ 100</code>
:Then recompile the kernel. After i changed it on my ThinkPad {{A30}} (under SuSE 9.2 and 9.3) and recompiling the kernel the high pitch noise is gone away.

* Omar Yasin: Worked on my {{R52}}, thanks.

* [[User:Thinker|Thinker]]: In modern kernels this constant is in the kernel configuration {{kernelconf|CONFIG_HZ|Processor type and features||Timer Frequency|||||}}.

* [[User:sklnd|sklnd]]: As of 2.6.21, enabling a tickless kernel (CONFIG_NO_HZ) seems to fix the sound issue on the X60. This also has the added benefit of causing the kernel to wake up less, which will improve battery life.

===Prevent idling===

Indirectly avoid power saving states by making sure the CPU is rarely idle:

* Paul RIVIER: Here is a really simple workaround. C3 / C4 states are mainly called when the cpu freq is higher than required, for example if your cpufreqd is lazy to slow down the frequency but quick to raise it. That is why I use powernowd with the builtin "passive" mode, which is lazy for raising frequency, but quick to go back to the lowest. Now I don't hear them as often as before, as I avoid C3/C4 states at high frequency.

* The problem also occurs on my {{X41}} with 2.6.11. Setting up [[How to make use of Dynamic Frequency Scaling|frequency scaling]] with the <code>ondemand</code> governor makes things a lot better, as the processor does not stay with the maximum frequency when in idle mode. It can be still heard sometimes, though.

* On a {{T43}} the noise was gone after dropping cpufreqd and switching to the ondemand governor - maybe because of the high sampling rate? (used the default: 10ms)

===Change the processor voltage===

Reducing the processor voltage (when possible) may decrease or eliminate the noise. On one ThinkPad {{T43}}, [[Pentium M undervolting and underclocking|undervolting the Pentium M processor]] eliminated the high-pitched noise. Compared to the other solutions this has the benefit of lower power consumption, both due to the undervolting itself and because there is no need to forbid high APCI CPU power saving modes.

===Kernel BIOS options===

Adding acpi_sleep=s3_bios and pci=bios as boot parameters significantly reduced the pitch noise on a T61. Seems to be the best solution so far, without losing battery capacity. If ondemand governor is enabled as well, the noise is almost gone.--[[User:Mozz|Mozz]] 13:14, 18 January 2008 (CET)

===Kernel Update===

The recent kernel update in Ubuntu 8.04 from 2.6.24-19 to 2.6.24-21 made the noise disappear on my T61. With the old kernel the sound was very audible when running on battery power, although setting the kernel BIOS options as specified in the paragraph above made it somewhat bearable. Now I can barely hear anything with the default startup options, even with my ear close to the laptop.

==Solutions for screen brightness related sounds==

===Disable BIOS brightness control===

The sound starts when on batteries as the BIOS automatically reduces screen brightness. To disable this, simply switch Config>Display>Brightness from
Normal to High. See also [[User:Piccobello/Hissing sound on battery|here]].

==Other solutions==

===Disable UltraBay===
*Naheed Vora: My {{T41}} (2373-268) started to give high pitch noise ocassionally, when I upgraded to 2.6.11 kernel. I tried to unload lot of modules but finally figured out that disabling bay stops the noise. If you have [[ibm-acpi]], do (need a cleaner solution): {{cmduser|echo eject >/proc/acpi/ibm/bay}} .

===Disable IrDA===
*Mike Perry: I was able to cure an intermittent high-pitched whine on both my {{X24}} and {{X40}} by disabling the Infrared port.

===Disable the Linuxant Modem Driver===
*Joern Heissler: I made another experience. I played around with linuxant conexant [[Modem Devices|modem]] drivers. After loading them I got some noise on my {{T42p}}.

===Media Player paused===
*Eilif Muller: On my {{R52}} the high-pitched noises go away if I load XMMS, play something then pause it.
*Jacob: On my {{T43}} DGU it goes away if I open mplayerc.exe and press play then pause it. This is the high-pitched noise that only shows up when I'm on battery.
*butcom: On my {{X60 Tablet}}, this tip works in Windows as well with Media Player Classic or Windows Media Player. Just open either program, start playing any music file and pause it and the screeching noise stops.

''I'd guess that the above tip works as when xmms or similar is running, it is uncompressing compressed audio/video, which is a processor intensive action. Keeping this paused means that the app won't 'let go' of the processor, forcing it to stay up and running, which stops it entering the higher powersave modes.''

===nice yes===

Run the command:
{{cmduser|nice yes > /dev/null}}.

This is a good way to test whether the processor is causing the interference, since it forces the CPU to stay at full power. Of course, this will make your system get warm, and probably turn on the fan, as well as eating power.

===Upgrade BIOS===
On a ThinkPad {{X60s}}, [[BIOS_Upgrade|upgrading the BIOS]] to version 1.06 eliminated the high pitch noise when running on battery.

On a ThinkPad {{R60}}, [[BIOS_Upgrade|upgrading the BIOS]] to version 2.19 eliminated the voice also.

===Disable USB===
On one {{T43}} and one {{X60}}, (partially) disabling USB using {{cmdroot|rmmod uhci_hcd}} significantly reduced the noise. Also, on a {{T60}} this trick worked well, doing ''rmmod/modprobe'' twice wiped the noise permanently.

This is likely a CPU-induced noise case, as disabling USB UHCI will reduce a lot the amount of busmaster activity while the computer is idle, and thus has a direct effect on the need for ACPI C-state transitions from C3/C4 to C2 or lower states in a {{T43}} or {{X60}}.

*syscrash: Plugging in my USB mouse has completely solved the problem for me.
*lorien: Plugging USB mouse helped me too {{T61}}
*telofy: Disabling USB "solved" the problem; so does disabling the CPU idle setting in the BIOS on my {{X200s}}.

===Suspend USB===
*Stefan Ott: On my X41, the noise seems to have stopped since I enabled "USB selective suspend/resume and wakeup" (CONFIG_USB_SUSPEND).
*babrodtk: This approach worked with an R60 as well.