ThinkWiki - User contributions [en]

Installing Ubuntu 7.10 (Gutsy Gibbon) on a ThinkPad T61

2008-01-01T10:38:24Z

Schradt: /* Nvidia Quadro N140 and 570M: */ brightness control now working

==Introduction==

This document outlines configuring Ubuntu 7.10 (Gutsy Gibbon) on your Thinkpad T61. Most items will work out of the box and a base install should provide you with a completely working system. Due to the modular nature of the T61 there are many different configuration, please read carefully and only make the changes specific to your system.

Feel free to update this Wiki with your information however please ask questions on the Talk page.

==Installation Notes ==

*If booting with the live CD gives you a blank screen you should select the "Safe Graphics" menu choice.

== Display/Video ==

=== Accelerated Video and Desktop Effects ===
'''Intel''' 2D and 3D accelerated video work out of the box.

Due to [https://bugs.launchpad.net/xorg-server/+bug/111257 | bug 111257], compiz is disabled on the Intel i965 based video cards. All systems updated after 11/24/2007 should be fixed.

'''Nvidia''' 2D video works out of the box, to enable accelerated 3D support click System->Administration->Restricted Drivers Manager {{NOTE| If the Restricted Drivers Manager fails to install the driver you can use the Envy tool from: http://albertomilone.com/nvidia_scripts1.html. This tool is unsupported and the only supported method of installing the Nvidia drivers is via Synaptics and the Restricted Drivers Manager}}

===Multiple Monitors===

If you previously used Xinerama this is no longer a supported option, you should use one of the tools described below to configure dual displays.

====Nvidia N140m:====

When using the default drivers (The open source "nv" drivers) you can use Administration->"Screens and Graphics" to setup the second monitor

Using the proprietary drivers you must use the Nvidia tool located at Applications->System Tools-> Nvidia X Server Settings.

Note:
Twinview 'works' but doing anything with Twinview in fullscreen mode will cause it to span both monitors instead of just being on the second. This essencially kills the functionality of Twinview.

eg 1 --> you are an office working bringing your notebook to work to show a presentation but you can't use full screen.

eg 2 --> you want take your notebook to a friends house to watch a movie on his/her projector and fullscreen mode gets half displayed on the projector and half on the notebook monitor.

If you experience problems getting a working Twinview setup using nvidia-settings, please see [http://www.nvnews.net/vbulletin/showthread.php?t=101780 this thread]

====Intel X3100====

Plugging in an external monitor works, but is a clone of the built-in LCD by default. Using the Screens and Graphics tool located under Administration you can setup the second monitor as an extension of the existing screen or a clone for presentations, but it does not let you enable a second display on a second monitor.

'''Setting up dual monitors via the command line'''

If you like doing it via the command line and are using the Intel drivers or the open-source "nv" driver you can use this example (''Note all this should be possible using the Screens and Graphics tool so only make this change if you prefer the command line method''):

This is an example for a 1680x1050 built-in LCD and a 1600x1200 external LCD:
Add a "Virtual 3280 1200" line in the Display SubSection of the Screen Section in your xorg.conf:

Go to Applications -> Accessories -> Terminal and type the following:

{{cmdroot|sudo /etc/init.d/gdm stop}}

{{cmdroot|xrandr --output LVDS --auto}}

To set the built-in LCD to ouput 1680x1050

{{cmdroot|xrandr --output VGA --right-of LVDS}}

To extend the desktop

=== Fonts on High-Res Screens ===

On high-res screens (e.g. 15" 1680x1050), some users consider the default fonts too be too large ([https://bugs.launchpad.net/ubuntu/+source/gdm/+bug/99145 Launchpad bug report]). You can fix this by following these steps:

# Open System->Preferences->Appearance
# Select the "Fonts" tab
# Click the "Details" button (lower right)
# Adjust the Resolution down to 96dpi
# Make sure you have Subpixel (LCD) Smoothing enabled
# Save the preferences

If you also want small fonts on the GDM login window, you can do this:

# Open System->Administration->Login Window
# Select the 'Security' tab
# Click the 'Configure X-Server' button
# Append '-dpi 96' (without quotes) to the text in the 'Command' field
# Reboot the computer.

=== Brightness ===
====Intel X3100:====
The brightness controls should work out of the box on a fresh install.

====Nvidia Quadro N140 and 570M:====
With Nvidia Driver 169.07 (2007/12/20) the brightness controls do work out of the box on a Thinkpad T61 with Nvidia Quadro NVS 140M.

Previous Driver:
The brightness controls do not work out of the box, however you can switch to a virtual terminal (ctrl+alt+F1) increase or decrease the brightness and then switch back to X (ctrl+alt+F7) without disrupting the running applications (You should save anything open just to be safe). There is a new [http://www.nvidia.com/object/linux_display_ia32_169.04.html beta-driver (version 169.04)] by nvidia that fixes the brightness-controls. To install this driver use the Envy tool described above.

== Audio ==

=== Inextricably Linked to the Modem ===
Make sure that you have the modem enabled in the BIOS. If it is disabled, you may discover that your audio is also disabled. In this situation, your drivers may still load, but you will get an error message whenever you try to play audio.

===Enabling Audio controls===

By default, the sound may be disabled and the volume control buttons on the laptop (up by the ThinkVantage button) and the volume control applet (up by the clock) will not control the speaker volume (they actually control the microphone). To fix this:

# Right-click on the volume control applet (by the clock) and select "Open Volume Control"
# In the "Switches" tab, make sure "Headphone" and "Speaker" are both checked.
# Close the Volume control.
# Right-click on the volume control applet again and select "Preferences".
# Make sure the device is set to "HDA Intel (Alsa mixer)" and highlight the "PCM" option.
# Close the preferences.
# Select System->Preferences->Sound.
# In the "Default Mixer Tracks" section, make sure "PCM" is highlighted.
# Close the sound preferences.

You should now hear sound and be able to control the volume using the laptop buttons or volume applet.

A recent BIOS update [http://www-307.ibm.com/pc/support/site.wss/document.do?sitestyle=lenovo&lndocid=MIGR-67989] fixes the mute button, you can then configure it to mute/unmute audio in Keyboard Shortcuts.

===Microphone===

There have been reports that the microphone may not work, please add your input to the talk page [http://www.thinkwiki.org/wiki/Talk:Installing_Ubuntu_7.10_%28Gutsy_Gibbon%29_on_a_ThinkPad_T61#Microphone] and update this section when a consensus on the problem and solution has been reached.

===Sound Cracking===

There have been intermittent reports of users experiencing cracking when listening to audio. Here are a few possible solutions:

* Try to switch to the OSS driver in system => preference => sound => devices => Music and movies, select OSS - Open sound system (instead of ALSA)

* If this issue is only occurring for Rhythmbox go to Edit > Preferences > Playback > and Check "Use Crossfading Backend". Restart Rhythmbox and you should have better audio quality.

* Check that the microphone is muted and modify your mixer settings by moving items like PCM down halfway and see if the cracking goes away.

===Hissing===
Some users experience hissing during playback, and even when idle. To solve this mute the microphone when it is not in use:

# Run "alsamixer" in the terminal.
# Arrow over to "Mic", and hit "M" to mute.
# Arrow over to the first "Docking", and hit "M" to mute.
# Arrow to the first "Internal", and hit "M" to mute.

Now, make sure that "Headphone" and/or "Speaker" are _not_ muted, and that "PCM" is at a reasonable level (say ~70) so you don't make your ears bleed, and try playing something back. ''(<Esc> will exit alsamixer)''

== Modem ==

The modem works with the Linuxant drivers available at http://www.linuxant.com

==Bluetooth==
Bluetooth works out of the box. Pressing Fn-F5 once will enable bluetooth, disable wireless, pressing again, enable both and pressing one more time will disable bluetooth.

If you would like to set bluetooth state independently the script below determines the current bluetooth state and toggles the device on or off.

First create a new file named bluetooth-toggle:
{{cmdroot|sudo touch /usr/sbin/bluetooth-toggle}}

Now open a editor:
{{cmdroot|sudo gedit /usr/sbin/bluetooth-toggle}}

Paste the following script:

#!/bin/bash
cat /proc/acpi/ibm/bluetooth | awk '{ print $2 }' | while read line;
do
if [ $line == "enabled" ]; then
echo disable > /proc/acpi/ibm/bluetooth
else
echo enable > /proc/acpi/ibm/bluetooth
fi
break
done

Now set the execute permissions:
{{cmdroot|sudo chmod +x /usr/sbin/bluetooth-toggle}}

You can invoke the script out of the console by typing sudo bluetooth-toggle or create a menu icon by using the menu editor under preferences using gksudo bluetooth-toggle as command line.

== Fingerprint Reader ==

The reader works with ThinkFinger. General instructions available [http://www.thinkwiki.org/wiki/Integrated_Fingerprint_Reader here] and [https://wiki.ubuntu.com/ThinkFinger here].
Instructions in French available at http://doc.ubuntu-fr.org/materiel/thinkfinger

Note that ThinkFinger in it's current version does not work with KDE and Kubuntu in any way (it crashes KDM and is not integrated at all).

Prebuilt packages are available from jldugger using Launchpad's PPA:

Add the thinkfinger package repository by creating {{path|/etc/apt/sources.list.d/thinkfinger.list}} with these two lines:

deb http://ppa.launchpad.net/jldugger/ubuntu gutsy main restricted universe multiverse
deb-src http://ppa.launchpad.net/jldugger/ubuntu gutsy main restricted universe multiverse

Then update the package database and install packages:

{{cmduser|sudo apt-get update}}
{{cmduser|sudo apt-get install libpam-thinkfinger libthinkfinger-dev libthinkfinger-doc libthinkfinger0 thinkfinger-tools}}

After the package is installed edit {{path|/etc/pam.d/common-auth}} and replace the line

auth required pam_unix.so nullok_secure

with

auth sufficient pam_thinkfinger.so
auth required pam_unix.so try_first_pass nullok_secure

Edit {{path|/etc/modules}} and add the following line:

uinput

Load the module manually for this session:

{{cmduser| sudo modprobe uinput}}

Summary:
* Recording fingerprints works
* Login works
* The password must be entered to unlock a locked screensaver
* sudo works
* gksu and gksudo hang : for example it is necessary to run synaptic twice and enter your password upon failure. To be able to use the Finger print reader in the session subsequently, kill the hanging gksu/gksudo process. A workaround is editing the Gnome System Menu (alacarte) to specify sudo instead of gksu/gksudo for the launching command and choose type "Application in Terminal" : this opens an extra terminal window for each superuser application you want to use though.

== Trackpad scrolling ==

Trackpad scrolling works out of the box in the standard thinkpad way: Slide your finger up and down the very right edge of the trackpad.
Note that /etc/X11/xorg.conf will be changed and the edge scrolling will be disabled after running nvidia-xconfig , copy the trackpad section from the backup of xorg.conf

To enable using the middle mouse button to scroll, add the following lines to the "Configured Mouse" section in
{{path|/etc/X11/xorg.conf}}:

Option "EmulateWheel" "true"
Option "EmulateWheelButton" "2"

== Hibernate/Suspend ==

=== Blank screen fix for intel graphics cards===

This fix is for Intel Graphics Cards only.

You may get a blank screen when resuming from suspend or hibernate ([https://bugs.launchpad.net/ubuntu/+bug/134391 Launchpad bug report]). To fix this:

1) Go to the in Applications -> Accessories -> Terminal

2) Enter "sudo nautilus" without the quotation marks.

3) Go to {{path|/boot/grub/}}, backup and then edit {{path|menu.lst}} by adding "acpi_sleep=s3_bios" (no quotes) to the "defoptions" list so that it looks something like this:

## additional options to use with the default boot option, but not with the
## alternatives
## e.g. defoptions=vga=791 resume=/dev/hda5
# defoptions=quiet splash '''acpi_sleep=s3_bios'''

4) Once you have edited the line and added the acpi_sleep parameter, you need to run

<pre>sudo update-grub</pre>

in the terminal.

Note that if you get the blank screen upon resume, a quick-fix is to switch to a console (Ctrl-Alt-F1) and then back to X (Ctrl-Alt-F7). This will usually bring the display back to life. However, the long-term fix is to add the acpi_sleep parameter as shown above.

=== How to Suspend with nVidia 140m/570m ===

The suspend to RAM will work with the nVidia card and the proprietary drivers, but it requires some file editing. It did not work for me out of the box. Using the package manager, download and install the latest nVidia drivers (100.14.19+2.6.2.4-12.4 at time of writing). I also had to use the 2.6.22-12-generic kernel image (the 2.6.22-13 image did not work with this driver --- I'm assuming it has to match wit the nVidia version, but I am not an expert).

Once you have it installed and working, you have to make a change to {{path|/etc/default/acpi-support}}. Open the file in your favorite editor and change the following lines:

$ sudo nano /etc/default/acpi-support

{{path|/etc/default/acpi-support}}
# Should we save and restore state using the VESA BIOS Extensions?
SAVE_VBE_STATE=false
...
# Should we attempt to warm-boot the video hardware on resume?
POST_VIDEO=false
...
# Set the following to "platform" if you want to use ACPI to shut down
# your machine on hibernation
HIBERNATE_MODE=platform

This allowed me to suspend and resume, but after two suspends the wireless wouldn't work anymore. Theoretically, ACPI unloads the network drivers before suspending, but it doesn't seem to work correctly so I added these to the blacklist modules manually (in the same file as above:

{{path|/etc/default/acpi-support}}
# Add modules to this list to have them removed before suspend and reloaded
# on resume. An example would be MODULES="em8300 yenta_socket"
#
# Note that network cards and USB controllers will automatically be unloaded
# unless they're listed in MODULES_WHITELIST
MODULES="iwl4965 iwlwifi_mac80211 cfg80211"

Your wifi modules may be different. (I have the intel AGN wireless card -- I don't know if these modules are different for other cards.)

This allows me to suspend to ram; I haven't had any problems with it so far. I haven't gotten hibernate (suspend to disk) working, so there may be additional things you need to do for that. (I think part of my problem is that I don't have enough swap, but I don't care enough to actually fix it.)

If the system has been left in suspend off for a while, wireless might not reconnect at all (Thinkpad T61 8892-02U). Restarting netapplet
solves the problem.

{{path|/etc/default/acpi-support}}
# Add services to this list to stop them before suspend and restart them in
# the resume process.
STOP_SERVICES="netapplet"

/*The fix does not work for me. I have a T61 7664-17U(NVS 140m, 4965agn). The computers suspend, but when it wakes up it hangs up and I have to pull out the battery to restart it.*/

General hint: Do not install the package "hibernate" or "uswsusp" or the gnome-power-manager will fail to suspend/hibernate your computer. If you have installed the package don't forget to purge the configuration. (sudo apt-get remove hibernate --purge, uswsusp resp.)

The instructions for Intel video card recommends adding "acpi_sleep=s3_bios" to the kernel parameters in Grub configuration. According to a comment on [https://bugs.launchpad.net/ubuntu/+source/acpi/+bug/139089 Launchpad BUG 139089], the correct setting for Nvidia is "acpi_sleep=s3_mode". Once I changed this, Suspend to ram worked. I have the T61 6459-CTO.

== Items that work out of the box ==

'''Intel Video:''' 2D and 3D acceleration works

'''Nvidia:''' 2D works, 3D requires the installation of the proprietary drivers

'''Wireless:''' Atheros and Intel cards both tested.

'''Bluetooth:''' Tested with both a bluetooth headset and an HTC 8525

'''Network Card''' Intel 10/100/1000 tested

'''Firewire''' Tested with hard drive

'''Wireless switch'''

'''4-in-1 card reader'''

'''Webcam'''

'''Headphones''' You may need to enable Headphone out: Right-click on the volume control and select open volume control. Click the switches tab and then check the headphones box.

'''Keyboard Shortcuts:'''
* Fn-PgUp activates/deactivates the thinklight
* Fn-Up will trigger stop on a media player
* Fn-Down will toggle pause and play on a media player
* Fn-Left/Right go to prev/next tracks on a media player
* Fn-F2 properly locks the screen
* Fn-F3 shows remaining battery >>does not work on all machines<<
* Fn-F4 suspends (to ram)
* Fn-F12 hibernates (to disk)
* PrtSc opens the screenshot dialog

'''Docking Stations:'''

All docking station models should work and the following features have been tested:

* DVI or Analog video: You can switch to it using "Administration->Screens and Graphics", if you are using the proprietary Nvidia drivers you must use the Nvidia Control Panel.

* Network Pass-through

* Modem Pass-through

* USB ports: Connected upon docking

* PS/2 Ports

== Items that don't work ==

=== Interrupt problem (PROBABLY SOLVED) ===
This bug is supposed to be solved by updating the system BIOS to the [http://www-307.ibm.com/pc/support/site.wss/document.do?sitestyle=lenovo&lndocid=MIGR-67989 2.07]-Version (with 1.08 AMT). Still testing...
* https://bugs.launchpad.net/ubuntu/+source/linux-source-2.6.22/+bug/126369
* USB ports can end up temporarily disabled
* Wifi can break
* integrated cardreader can be disabled
* bluetooth can be disabled
* Setting IRQ's to "Auto" from factory default of "11" in the BIOS seems to help some people.
* The two USB ports on the left side of the computer may fail to connect storage devices during a session but will load them at boot up.
* booting with the "irqpoll" option seems to work for some people against the problem that usb-ports stop working.
* GLX (3d graphics) on intel 965 video card is broken: https://bugs.launchpad.net/ubuntu/+source/xserver-xorg-video-intel/+bug/120834

=== Wireless activity LED ===

The LED is not implemented in either the IWL4965 or Atheros drivers.

== Power consumption ==

Gutsy is the first version of Ubuntu to feature a tickless kernel (i386 only, not in AMD64 yet). Power consumption
can be monitored using the powertop tool under Ubuntu and using Lenovo battery monitor
under Windows.

$ sudo apt-get install powertop
$ sudo powertop

I couldn't find any difference in power consumption between the i386 tickless kernel (even with 70ms average sleep in C4)
and AMD64 kernel (2ms average sleep in C4). It would be expected that considerably less power would be consumed for the
i386 tickless kernel.

There is also a graph available by Right-clicking on the battery icon and selecting Power History.

These are the figures measured on a T61 15.4" 1680x1050 screen 7300 processor (2GHz) 2GB RAM, Intel X3100 graphics
with 4965 wifi, Bluetooth and UWB.

{| border=1 cellpadding=5
|-
| 12.3W
| Windows XP Pro, all radios on, about 50% brightness
|-
| 16.7W
| Gutsy, all radios on, 50% brightness
|-
| 19.6W
| Gutsy, all radios on, 100% brightness
|-
| 14.2W
| Gutsy, all radios on, 10% brightness
|-
| -1.0W
| Turning the physical radio switch to off on the front reduces power consumption by 1 watt.
|}

Adding the Nvidia card increases the laptops power requirements.

These are the figures measured on a T61 14" 1440x900 screen 2.2ghz Core2Duo 2GB RAM, Nvidia 140m video, IWL4965 wifi and Bluetooth (Disabled):

{| border=1 cellpadding=5
|-
| 18.3W
| Gutsy, all radios on, 50% brightness
|-
| 19.4W
| Gutsy, all radios on, 100% brightness
|-
| 16.0W
| Gutsy, all radios on, 10% brightness
|-
|}

[[Category: T61]] [[Category: Ubuntu 7.10]]

How to reduce power consumption

2007-06-27T18:51:47Z

Schradt: append to blacklist instead of replacing...

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, ...)
* 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

==Tools==
Arjan van de Ven's [http://www.linuxpowertop.org/ PowerTOP] utility
is a gold mine to improve energy efficiency. This tool helps to easily detect
the top power offenders, both userland and kernel modules, and sometime suggest
fixes accordingly.
PowerTOP users collected some [http://www.linuxpowertop.org/known.php tips & tricks]
and an informative [http://www.linuxpowertop.org/faq.php faq].

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

Beside CPU wakeups, disks spins are also power angry. 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).

==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 angry 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). If
it's not already on your distribution and you value power efficiency, you
may think about compiling it (or a more recent one) 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_CPU_FREQ_GOV_ONDEMAND
CONFIG_USB_SUSPEND
CONFIG_SND_AC97_POWER_SAVE
CONFIG_TIMER_STATS
CONFIG_ACPI_BATTERY
CONFIG_CPU_FREQ_STAT
# Not from the PowerTOP FAQ:
CONFIG_BLK_DEV_IO_TRACE
CONFIG_X86_ACPI_CPUFREQ
CONFIG_X86_SPEEDSTEP_CENTRINO
CONFIG_X86_SPEEDSTEP_ICH
CONFIG_X86_SPEEDSTEP_SMI
CONFIG_X86_ACPI_CPUFREQ
</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 et CONFIG_ACPI_DEBUG.

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

===Useful Patchs===

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).
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). See:
http://www.kernel.org/pub/linux/kernel/people/kristen/patches/SATA/alpm/

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 developpers
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 there] 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 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 min_power > /sys/class/scsi_host/host0/link_power_management_policy
echo min_power > /sys/class/scsi_host/host1/link_power_management_policy
echo 1500 > /proc/sys/vm/dirty_writeback_centisecs
</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,noatime / # and so on for all mounted fs
</code>

The laptop_mode reduce disk usage by regrouping 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.
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>

===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. If you have a recent hald version, you
can stop this polling when on battery:

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

If your hald is not recent enough, consider stopping it on battery.

==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.

==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.

On recent xrandr/xorg versions, you can disable the TV output when you're
not using it (it's known to consume power) :

<code>
xrandr --output TV -off
</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.

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 USB 1.1 device (unfortunately, the built-in bluetooth and fingerprint-reader are USB 1.1 devices), the USB 1.1 support can also be totaly avoided. On Debian and derivatives, just do:

<code>
echo "blacklist uhci_hcd" >> /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).

Seel also [[How to enable AC97 power saving]].

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

<code>
echo 1 > /sys/bus/pci/drivers/ipw2200/*/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 7
</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.

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

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

==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.

==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)
* ''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:Z60m]] [[Category:Z60t]] [[Category:Z61t]] [[Category:Z61e]] [[Category:TransNote]]

Problem with display remaining black after resume

2007-06-23T11:46:05Z

Schradt: /* Solution for ThinkPads with ATI graphic chips and Intel 915/945GM */

There has been a problem encountered where the display stays black on resuming from suspend.

The symptom might have you think first that your system hang up, but you will realize that your ThinkPad works and you can even reset it via {{key|Ctrl}}{{key|Alt}}{{key|Del}}.

==Affected Models==
*ThinkPad {{T41p}}, {{T42}}, {{T42p}}, {{T43}}, {{T43p}}, {{T60}}
*Thinkpad {{T23}}
*ThinkPad {{X21}}, {{X30}}, {{X31}}, {{X40}}, {{X41}}
*ThinkPad {{R31}}, {{R50e}}{{footnote|1}}, {{R50p}}, {{R51}} (with BIOS 1.11), {{R52}}, {{R60}}
*ThinkPad {{A30p}}
*ThinkPad {{390X}} (doesn't wake up; LCD backlight on, harddrive light remains on)
*ThinkPad {{Z60t}}, {{Z60m}}, {{Z61m}}, {{Z61e}}
*ThinkPad {{X60s}}, {{X60}}

==Affected Operating Systems==
*Linux (it's a kernel issue)
*FreeBSD (6.x at least)

==Solutions==
===Semi-Solution for ThinkPad X60 with damaged system after s2ram usage===
It happend when restarting a s2ram-session.

'''Symptom:''' Black screen with blinking "_" sign remaind. (without the ")

'''System status:''' HDD idle, fan running, everything else looks to wait for something to happen.

'''Semi-Solution:''' Booting with DVD-ROM and going through the installations menu,
where you choose "other" and "boot a installed system" (something like that). Gladly it works,
and OpenSuSE 10.1 comes up with 50% "failed" messages! I than shutdown properly, rebooted again
and had 100% "done" again, with no other things affected.

'''Further:''' Repairing with the DVD-ROM crashed massivly(!), so I selected "boot a installed system" as final
solution and it worked!

'''Unknown:''' Maybe the Solution for ThinkPads with 1400x1050 internal LCD and Intel 915GM will help,
because X60s and X60 are very familiar. (Not tested so far.)

(If this Problem is not right here, please edit and move.)

===Solution for ThinkPads with 1400x1050 internal LCD and Intel 915GM ===
see [[1400x1050 on Intel 915GM]].
===Solution for ThinkPads with ATI graphic chips and Intel 915/945GM ===

Affected models include {{X60s}}, {{R60}} and {{T60}}.

This soluton also applies to T42 with Intel 855 and ATI 9600 M10.

One solution may be to provide the {{bootparm|acpi_sleep|s3_bios}} kernel parameter in your kernel parameter line.

For grub this would look like this:

title Linux, kernel 2.6.11-1-686
root (hd0,0)
kernel /boot/vmlinuz-2.6.11-1-686 root=/dev/hda1 ro acpi_sleep=s3_bios
initrd /boot/initrd.img-2.6.11-1-686
savedefault
boot

For lilo it would look like this:

image=/boot/vmlinuz
append="acpi_sleep=s3_bios"

The actual process of going to sleep is then managed through a sleep script; as a start, see the {{path|sleep.sh}} script in the Extreme Graphics 2 section below, but note the following comments:

In [[:Category:OpenSUSE|OpenSUSE]] 10.1 (at least on a T43p), it's necessary to override the default options for s2ram if you're using the newer ATI driver. This can be done putting {{bootparm|SUSPEND2RAM_FORCE|"yes"}} and {{bootparm|SUSPEND2RAM_ACPI_SLEEP|"3"}} in {{path|/etc/powersave/sleep}}.

In {{Ubuntu}} or {{Kubuntu}}, it may be necessary to modify {{path|/etc/default/acpi-support}}. In that file, make sure that {{path|ACPI_SLEEP}} is uncommented and set to true. With ATI chips, also make sure that {{path|SAVE_VBE_STATE}} is uncommented and set to true; with Intel chips, on the other hand, ensure that nothing is done with respect to VBE--no reposts, no state saves.

In {{Fedora}}, it may be necessary with the Intel chips to edit the {{path|resume_video()}} function in {{path|/etc/pm/functions-intel}} to comment out the VBE post and restore. (As of FC6 these seem to be pre-commented out.) Also, the laptop, after waking up, may go back to sleep immediately or whenever the AC adapter is disconnected. When this happens, it's caused by a bug in the HAL daemon that incorrectly reports certain ACPI events. This is a known problem and a simple workaround is described [http://live.gnome.org/GnomePowerManager/Faq#head-b8b1280115b0a51c2cc27b13a57121130ebf36cb here].

{{NOTE|It is possible this method will not work if the laptop is docked. It is also possible that the cited workaround for the HAL daemon bug will not work on some machines. A kludgier workaround in this event is to kill the HAL daemon on suspend. This necessitates the resuscitation of GPM upon resume.}}

Another solution is to use vbetool. If you are using {{Debian}} with the hibernate package, uncomment "EnableVbetool yes" in {{path|/etc/hibernate/hibernate.conf}} (or {{path|/etc/hibernate/ram.conf}}).

----

On '''T60 2007-CTO''' (Core2Duo 2Ghz, 2GB Ram, ATI X1400) the screen stayed blank after suspend-to-ram until I set '''vga=0''' in lilo.conf.

Working config:
Linux 2.6.21.5
fglrx 8.37.6
debian etch:
powersaved 0.14.0-5:
UNLOAD_MODULES_BEFORE_SUSPEND2DISK="usb_storage ohci_hcd uhci_hcd ehci_hcd ipw3945 pcmcia yenta_socket rsrc_nonstatic pcmcia_core"
UNLOAD_MODULES_BEFORE_SUSPEND2RAM="usb_storage ohci_hcd uhci_hcd ehci_hcd ipw3945 pcmcia yenta_socket rsrc_nonstatic pcmcia_core"
hibernate:
SwitchToTextMode yes
lilo.conf:
vga=0

"EnableVbetool yes" and other suggestions didn't work for me.

For suspend-to-disk, don't load fglrx in initrd.

----

===Solution for ThinkPads with Intel Extreme Graphics 2===
{{NOTE|
On [[:Category:X40|X40]]s/[[:Category:X41|X41]]s - even with Intel Extreme Graphics - and for [[:Category:R52|R52]]s with Intel Graphics Media Accelerator 900 the [[Problem with display remaining black after resume#Solution for ThinkPads with ATI graphic chips|solution for ATI graphics chips]] above is reported to work. In this case, make sure no changes to VBE are made, especially no state saves and no reposts.}}

The following solution should work on 865G, 865GV, 855GM, 855GME, 852GME chipsets.
*First of all, '''do not''' use the {{bootparm|acpi_sleep|s3_bios}} kernel parameter.
*Second, completely remove framebuffer support from your kernel. If it's built as modules, it is important that they do not get loaded at all.
*Before suspending, change to a console and safe the video state with {{cmdroot|cat /proc/bus/pci/00/02.0 > /tmp/video_state}}.
*On resume, restore the video state with {{cmdroot|cat /tmp/video_state > /proc/bus/pci/00/02.0}} and change back to X.
*For Debian Etch 4.0 on R50e just make following changes to /etc/default/acpi-support:
#SAVE_VBE_STATE=true
#VBESTATE=/var/lib/acpi-support/vbestate
#POST_VIDEO=true
SAVE_VIDEO_PCI_STATE=true

*For a R50e the only thing needed to make suspend to ram work in Ubuntu 6.06 is adding
Option "VBERestore" "yes"
to the <tt>Device</tt> section in your {{path|/etc/X11/xorg.conf}}, and the example script below.

The following example {{path|/etc/acpi/actions/sleep.sh}} script shows how to integrate the according lines.

#!/bin/bash

# change to console 1
FGCONSOLE=`fgconsole`
chvt 6

# safe video state
cat /proc/bus/pci/00/02.0 > /tmp/video_state

# sync filesystem
sync

# sync hardware clock with system time
hwclock --systohc

# go to sleep
echo -n 3 > /proc/acpi/sleep

# waking up
# restore system clock
hwclock --hctosys

# restore video state
cat /tmp/video_state > /proc/bus/pci/00/02.0

# change back to X
chvt $FGCONSOLE

# clean up behind us
rm /tmp/video_state

With Ubuntu 6.10 on a [[:Category:R51|R51 (2887-32G)]] I ''just'' (as none of the other tricks above) had to add {{bootparm|fb|false}} to the kernel line in {{path|/etc/grub/menu.lst}} and edit {{path|/etc/defaults/acpi-support}} this way:

SAVE_VBE_STATE=false
POST_VIDEO=false
SAVE_VIDEO_PCI_STATE=true
USE_DPMS=false
DOUBLE_CONSOLE_SWITCH=false

===Solution for ThinkPads with Intel I830 Chipset===
The following solution worked for me on an X30 with I830M chipset with kernel >= 2.6.16.
*this works with vesafb and also with intelfb frambuffer support.
The following example {{path|/etc/acpi/actions/sleep.sh}} script shows how to integrate the according lines.

#!/bin/bash

FGCONSOLE=`fgconsole`
chvt 8
sync
hwclock --systohc

echo -n "mem" > /sys/power/state

hwclock --hctosys
vbetool post

if [ "$FGCONSOLE" -ge "7" ] ; then
chvt $FGCONSOLE
else
chvt 7
chvt $FGCONSOLE
fi
===Solution for ThinkPads with ATI graphic (and possibly other) chips and FreeBSD===

The FreeBSD acpi(4) manpage mentions a tunable parameter, "hw.acpi.reset_video":

hw.acpi.reset_video
Reset the video adapter from real mode during the resume path.
Some systems need this help, others have display problems if it
is enabled. Default is 0 (disabled).

This tunable can be set by adding the following line to your FreeBSD machine's /boot/loader.conf file:

hw.acpi.reset_video="1"

And rebooting your machine. Hopefully, the next time you resume from a suspend, you'll see your video again. This solution doesn't appear to be specific to ATI hardware in any way, so I presume it would be helpful for video chipsets other than ATI, as well.

If this entry doesn't help you, you might consider searching in the [http://lists.freebsd.org/pipermail/freebsd-mobile/ FreeBSD-Mobile email-list archive] for more insight.

{{footnotes|
#If you have this problem with R50e and the above solution doesn't work, try switching to console first. An example sleep script can be found [[How to configure acpid|here]].
}}

===Solution using s2ram for Intel 915/945GM===

Just using the "s2ram -f -p" command from the uswsusp package will work from within X, at least on a {{Z61e}}.

Problem with display remaining black after resume

2007-06-23T11:39:12Z

Schradt: /* Solution for ThinkPads with ATI graphic chips and Intel 915/945GM */

There has been a problem encountered where the display stays black on resuming from suspend.

The symptom might have you think first that your system hang up, but you will realize that your ThinkPad works and you can even reset it via {{key|Ctrl}}{{key|Alt}}{{key|Del}}.

==Affected Models==
*ThinkPad {{T41p}}, {{T42}}, {{T42p}}, {{T43}}, {{T43p}}, {{T60}}
*Thinkpad {{T23}}
*ThinkPad {{X21}}, {{X30}}, {{X31}}, {{X40}}, {{X41}}
*ThinkPad {{R31}}, {{R50e}}{{footnote|1}}, {{R50p}}, {{R51}} (with BIOS 1.11), {{R52}}, {{R60}}
*ThinkPad {{A30p}}
*ThinkPad {{390X}} (doesn't wake up; LCD backlight on, harddrive light remains on)
*ThinkPad {{Z60t}}, {{Z60m}}, {{Z61m}}, {{Z61e}}
*ThinkPad {{X60s}}, {{X60}}

==Affected Operating Systems==
*Linux (it's a kernel issue)
*FreeBSD (6.x at least)

==Solutions==
===Semi-Solution for ThinkPad X60 with damaged system after s2ram usage===
It happend when restarting a s2ram-session.

'''Symptom:''' Black screen with blinking "_" sign remaind. (without the ")

'''System status:''' HDD idle, fan running, everything else looks to wait for something to happen.

'''Semi-Solution:''' Booting with DVD-ROM and going through the installations menu,
where you choose "other" and "boot a installed system" (something like that). Gladly it works,
and OpenSuSE 10.1 comes up with 50% "failed" messages! I than shutdown properly, rebooted again
and had 100% "done" again, with no other things affected.

'''Further:''' Repairing with the DVD-ROM crashed massivly(!), so I selected "boot a installed system" as final
solution and it worked!

'''Unknown:''' Maybe the Solution for ThinkPads with 1400x1050 internal LCD and Intel 915GM will help,
because X60s and X60 are very familiar. (Not tested so far.)

(If this Problem is not right here, please edit and move.)

===Solution for ThinkPads with 1400x1050 internal LCD and Intel 915GM ===
see [[1400x1050 on Intel 915GM]].
===Solution for ThinkPads with ATI graphic chips and Intel 915/945GM ===

Affected models include {{X60s}}, {{R60}} and {{T60}}.

This soluton also applies to T42 with Intel 855 and ATI 9600 M10.

One solution may be to provide the {{bootparm|acpi_sleep|s3_bios}} kernel parameter in your kernel parameter line.

For grub this would look like this:

title Linux, kernel 2.6.11-1-686
root (hd0,0)
kernel /boot/vmlinuz-2.6.11-1-686 root=/dev/hda1 ro acpi_sleep=s3_bios
initrd /boot/initrd.img-2.6.11-1-686
savedefault
boot

For lilo it would look like this:

image=/boot/vmlinuz
append="acpi_sleep=s3_bios"

The actual process of going to sleep is then managed through a sleep script; as a start, see the {{path|sleep.sh}} script in the Extreme Graphics 2 section below, but note the following comments:

In [[:Category:OpenSUSE|OpenSUSE]] 10.1 (at least on a T43p), it's necessary to override the default options for s2ram if you're using the newer ATI driver. This can be done putting {{bootparm|SUSPEND2RAM_FORCE|"yes"}} and {{bootparm|SUSPEND2RAM_ACPI_SLEEP|"3"}} in {{path|/etc/powersave/sleep}}.

In {{Ubuntu}} or {{Kubuntu}}, it may be necessary to modify {{path|/etc/default/acpi-support}}. In that file, make sure that {{path|ACPI_SLEEP}} is uncommented and set to true. With ATI chips, also make sure that {{path|SAVE_VBE_STATE}} is uncommented and set to true; with Intel chips, on the other hand, ensure that nothing is done with respect to VBE--no reposts, no state saves.

In {{Fedora}}, it may be necessary with the Intel chips to edit the {{path|resume_video()}} function in {{path|/etc/pm/functions-intel}} to comment out the VBE post and restore. (As of FC6 these seem to be pre-commented out.) Also, the laptop, after waking up, may go back to sleep immediately or whenever the AC adapter is disconnected. When this happens, it's caused by a bug in the HAL daemon that incorrectly reports certain ACPI events. This is a known problem and a simple workaround is described [http://live.gnome.org/GnomePowerManager/Faq#head-b8b1280115b0a51c2cc27b13a57121130ebf36cb here].

{{NOTE|It is possible this method will not work if the laptop is docked. It is also possible that the cited workaround for the HAL daemon bug will not work on some machines. A kludgier workaround in this event is to kill the HAL daemon on suspend. This necessitates the resuscitation of GPM upon resume.}}

Another solution is to use vbetool. If you are using {{Debian}} with the hibernate package, uncomment "EnableVbetool yes" in {{path|/etc/hibernate/hibernate.conf}} (or {{path|/etc/hibernate/ram.conf}}).

----

On '''T60 2007-CTO''' (Core2Duo 2Ghz, 2GB Ram, ATI X1400) the screen stayed blank after suspend-to-ram until I set '''vga=0''' in lilo.conf.

Working config:
Linux 2.6.21.5
fglrx 8.37.6
debian etch:
powersaved 0.14.0-5
hibernate: SwitchToTextMode yes
lilo.conf: vga=0

"EnableVbetool yes" and other suggestions didn't work for me.

For suspend-to-disk, don't load fglrx in initrd.

----

===Solution for ThinkPads with Intel Extreme Graphics 2===
{{NOTE|
On [[:Category:X40|X40]]s/[[:Category:X41|X41]]s - even with Intel Extreme Graphics - and for [[:Category:R52|R52]]s with Intel Graphics Media Accelerator 900 the [[Problem with display remaining black after resume#Solution for ThinkPads with ATI graphic chips|solution for ATI graphics chips]] above is reported to work. In this case, make sure no changes to VBE are made, especially no state saves and no reposts.}}

The following solution should work on 865G, 865GV, 855GM, 855GME, 852GME chipsets.
*First of all, '''do not''' use the {{bootparm|acpi_sleep|s3_bios}} kernel parameter.
*Second, completely remove framebuffer support from your kernel. If it's built as modules, it is important that they do not get loaded at all.
*Before suspending, change to a console and safe the video state with {{cmdroot|cat /proc/bus/pci/00/02.0 > /tmp/video_state}}.
*On resume, restore the video state with {{cmdroot|cat /tmp/video_state > /proc/bus/pci/00/02.0}} and change back to X.
*For Debian Etch 4.0 on R50e just make following changes to /etc/default/acpi-support:
#SAVE_VBE_STATE=true
#VBESTATE=/var/lib/acpi-support/vbestate
#POST_VIDEO=true
SAVE_VIDEO_PCI_STATE=true

*For a R50e the only thing needed to make suspend to ram work in Ubuntu 6.06 is adding
Option "VBERestore" "yes"
to the <tt>Device</tt> section in your {{path|/etc/X11/xorg.conf}}, and the example script below.

The following example {{path|/etc/acpi/actions/sleep.sh}} script shows how to integrate the according lines.

#!/bin/bash

# change to console 1
FGCONSOLE=`fgconsole`
chvt 6

# safe video state
cat /proc/bus/pci/00/02.0 > /tmp/video_state

# sync filesystem
sync

# sync hardware clock with system time
hwclock --systohc

# go to sleep
echo -n 3 > /proc/acpi/sleep

# waking up
# restore system clock
hwclock --hctosys

# restore video state
cat /tmp/video_state > /proc/bus/pci/00/02.0

# change back to X
chvt $FGCONSOLE

# clean up behind us
rm /tmp/video_state

With Ubuntu 6.10 on a [[:Category:R51|R51 (2887-32G)]] I ''just'' (as none of the other tricks above) had to add {{bootparm|fb|false}} to the kernel line in {{path|/etc/grub/menu.lst}} and edit {{path|/etc/defaults/acpi-support}} this way:

SAVE_VBE_STATE=false
POST_VIDEO=false
SAVE_VIDEO_PCI_STATE=true
USE_DPMS=false
DOUBLE_CONSOLE_SWITCH=false

===Solution for ThinkPads with Intel I830 Chipset===
The following solution worked for me on an X30 with I830M chipset with kernel >= 2.6.16.
*this works with vesafb and also with intelfb frambuffer support.
The following example {{path|/etc/acpi/actions/sleep.sh}} script shows how to integrate the according lines.

#!/bin/bash

FGCONSOLE=`fgconsole`
chvt 8
sync
hwclock --systohc

echo -n "mem" > /sys/power/state

hwclock --hctosys
vbetool post

if [ "$FGCONSOLE" -ge "7" ] ; then
chvt $FGCONSOLE
else
chvt 7
chvt $FGCONSOLE
fi
===Solution for ThinkPads with ATI graphic (and possibly other) chips and FreeBSD===

The FreeBSD acpi(4) manpage mentions a tunable parameter, "hw.acpi.reset_video":

hw.acpi.reset_video
Reset the video adapter from real mode during the resume path.
Some systems need this help, others have display problems if it
is enabled. Default is 0 (disabled).

This tunable can be set by adding the following line to your FreeBSD machine's /boot/loader.conf file:

hw.acpi.reset_video="1"

And rebooting your machine. Hopefully, the next time you resume from a suspend, you'll see your video again. This solution doesn't appear to be specific to ATI hardware in any way, so I presume it would be helpful for video chipsets other than ATI, as well.

If this entry doesn't help you, you might consider searching in the [http://lists.freebsd.org/pipermail/freebsd-mobile/ FreeBSD-Mobile email-list archive] for more insight.

{{footnotes|
#If you have this problem with R50e and the above solution doesn't work, try switching to console first. An example sleep script can be found [[How to configure acpid|here]].
}}

===Solution using s2ram for Intel 915/945GM===

Just using the "s2ram -f -p" command from the uswsusp package will work from within X, at least on a {{Z61e}}.