How to make use of Graphics Chips Power Management features

2006-02-05T21:01:09Z

Alex77: /* Activation */

=ATI Radeon Mobility chips=

==Power saving with a framebuffer console==
In order to use the dynamic GPU clock-scaling similar to what X.org has, you need to use the radeonfb kernel module. You'll need to enable the '''CONFIG_FB_RADEON''' in your kernel configuration. If setup correctly you should see something like the following in your kernel log:
radeonfb: Dynamic Clock Power Management enabled

==Using the X.org Radeon driver==
===Activation===
The xorg X server has support for a power saving feature from ATI called PowerPlay. Xorg calls this feature DynamicClocks. It can be enabled in the server by adding '''Option "DynamicClocks" "on"''' in the '''Device''' section in {{path|/etc/X11/xorg.conf}}

Section "Device"
Identifier "Videocard0"
Driver "radeon"
VendorName "IBM ThinkPad"
BoardName "ATI Radeon Mobility M9"
'''Option "DynamicClocks" "on"'''
EndSection

With this option enabled, the X11 server should print ({{path|/var/log/Xorg.0.log}}):

(**) RADEON(0): Option "DynamicClocks" "on"
(II) RADEON(0): Dynamic Clock Scaling Enabled

You do not need to do anything else, it dynamically manages the power consumption itself.

{{NOTE|Enabling DynamicClocks crashes some models. If the CPU is entering one of the lower power states (C3 or lower) during Xorg startup the display may stay black. As a workaround disable DynamicClocks in Xorg and use [[Rovclock]] instead. But it does not scale the clocks to match the workload. Update 5/2/2006: Seems fixed in Xorg6.9}}

===Problem with <tt>vbetool</tt>===

When <tt>vbetool</tt> is used to restore the display state (as done by some suspend/resume scripts), the setting of <tt>DynamicClocks</tt> is forgotten and the GPU will consume more power until the next X server startup. You can manually enable DynamicTools again by starting a blank second X server (e.g., by running {{cmdroot|X :1}}) and then exiting it via {{key|Ctrl}}{{key|Alt}}{{key|Backspace}}.

===Problem with suspend-to-disk===

Upon resume from suspend-to-disk, the setting of <tt>DynamicClocks</tt> is forgotten and the GPU will consume more power until the next X server startup. You can manually enable DynamicClocks again by starting a blank second X server (e.g., by running {{cmdroot|X :1}}) and then exiting it via {{key|Ctrl}}{{key|Alt}}{{key|Backspace}}.

If you're using the hibernate script that's part of [[Software Suspend 2]], setting UseDummyXServer to yes in {{path|hibernate.conf}} automatically starts a second X server, hence enabling DynamicClocks again. (Remember to disable UseDummyXServer if you switch to the [[fglrx]] driver, otherwise your computer will hang upon resume.)

Note: When using the [[Synaptics TouchPad driver for X]] with the SHMConfig-Option set to true in {{path|xorg.conf}}, starting a second X server breaks the Shared Memory and the touchpad can't be configured with {{cmd|synclient|}} any longer. Starting the dummy X server with a different xorg.conf file is a solution to this, a patch can be found in the [http://bugzilla.suspend2.net/show_bug.cgi?id=138 suspend2 bugzilla].

===Debian Notes===
If your {{Debian}} doesn't have Xorg, yet, see [http://incubator.vislab.usyd.edu.au/roller/page/Steve/20040909 Installing a non-intrusive X.org server on Debian].

Sarge backports are available from [http://www.backports.org/ here] or [http://people.debian.org/~nobse/xorg-x11/ here].

You can also add the following line to your repository list:
deb http://people.debian.org/~nobse/xorg-x11/ sarge main

==Using the ATI proprietary driver==

Versions 8.19.10 and higher of the ATI [[fglrx]] driver support "PowerPlay", which "allows for the user to switch between power consumption modes".

To list available modes do:
:{{cmdroot|aticonfig --list-powerstates}}
:{{cmdresult|   core/mem     [flags]}}
:{{cmdresult|---------------}}
:{{cmdresult|1: 105/122 MHz  [low voltage]}}
:{{cmdresult|2: 209/182 MHz  [low voltage]}}
:{{cmdresult|3: 297/230 MHz  [default state]}}

(Strangely, the same ThinkPad {{T43}} with [[ATI Mobility Radeon X300]] running [[fglrx]] 8.19.10 sometimes gives other, non-sensical results, perhaps due to interaction with [[rovclock]].)

To changing the power mode on the fly:
:{{cmdroot|1=aticonfig --set-powerstate=2 --effective=now}}

Limitations (as of [[fglrx]] 8.19.10):
* You can't set the power state in {{path|/etc/X11/xorg.conf}} .
* You can't activate power saving when using dual-head mode (e.g., LCD+CRT).

{{NOTE|[[fglrx]] power saving is not compatible with the [[Rovclock]] utility. Setting power saving mode using both [[fglrx]] and [[Rovclock]] results in an unusably slow desktop.}}

==External sources==
*[http://www.ati.com/products/pdf/powerplaywp2.pdf Marketing information from ATI]

=Other graphics chips=
No instructions are presently known for other chips.

[[Category:G40]] [[Category:G41]] [[Category:R32]] [[Category:R40]] [[Category:R40e]] [[Category:R50]] [[Category:R50e]] [[Category:R50p]] [[Category:R51]] [[Category:R52]] [[Category:T30]] [[Category:T40]] [[Category:T40p]] [[Category:T41]] [[Category:T41p]] [[Category:T42]] [[Category:T42p]] [[Category:T43]] [[Category:T43p]]

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How to make use of Graphics Chips Power Management features