need to turn off extra "Switchable graphics" GPU

[Tuukka Hastrup]

Some laptops such as this Acer Travelmate 8371G (Timeline) have two graphics adapters (Intel 4500MHD and ATI HD 4330). There are two BIOS settings: "Switchable graphics" and "Discrete graphics". With the latter option, only the ATI GPU is in use, but with the former option, *both* GPUs are powered on by default. Neither of these options is good for battery runtime.

Fortunately, Maverick kernel has the vga_switcheroo module enabled and it supports this laptop. What's missing by default is the command "echo OFF > /sys/kernel/debug/vgaswitcheroo/switch", which is needed to turn off the discrete GPU.

On the 8371G here, "Switchable graphics" originally gave some 2 hours of battery use, "Discrete graphics" gives some 3 hours of battery use, and "Switchable graphics" with this module loaded gives some 4 hours of battery use.

ProblemType: Bug
Architecture: i386
ArecordDevices:
 **** List of CAPTURE Hardware Devices ****
 card 0: Intel [HDA Intel], device 0: ALC269 Analog [ALC269 Analog]
   Subdevices: 1/1
   Subdevice #0: subdevice #0
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: tuukka 1878 F.... pulseaudio
CRDA: Error: [Errno 2] Tiedostoa tai hakemistoa ei ole
Card0.Amixer.info:
 Card hw:0 'Intel'/'HDA Intel at 0xf4500000 irq 22'
   Mixer name : 'Realtek ALC269'
   Components : 'HDA:10ec0269,10250284,00100004'
   Controls : 21
   Simple ctrls : 12
Date: Thu Sep 24 16:28:44 2009
DistroRelease: Ubuntu 9.10
HibernationDevice: RESUME=UUID=3a0cc818-d22b-4df4-9947-61373f45494c
MachineType: Acer TravelMate 8371
Package: linux-image-2.6.31-10-generic 2.6.31-10.35
ProcCmdLine: BOOT_IMAGE=/boot/vmlinuz-2.6.31-10-generic root=UUID=58fdc759-1719-40df-b6b6-1902991b8bba ro quiet splash
ProcEnviron:
 PATH=(custom, user)
 LANG=fi_FI.UTF-8
 SHELL=/bin/bash
ProcVersionSignature: Ubuntu 2.6.31-10.35-generic
RelatedPackageVersions:
 linux-backports-modules-2.6.31-10-generic N/A
 linux-firmware 1.19
SourcePackage: linux
Uname: Linux 2.6.31-10-generic i686
dmi.bios.date: 08/05/2009
dmi.bios.vendor: Acer
dmi.bios.version: V1.11
dmi.board.asset.tag: Base Board Asset Tag
dmi.board.name: TravelMate 8371
dmi.board.vendor: Acer
dmi.board.version: PSMBOU-1234567
dmi.chassis.asset.tag: None
dmi.chassis.type: 10
dmi.chassis.vendor: Acer
dmi.chassis.version: None
dmi.modalias: dmi:bvnAcer:bvrV1.11:bd08/05/2009:svnAcer:pnTravelMate8371:pvrV1.11:rvnAcer:rnTravelMate8371:rvrPSMBOU-1234567:cvnAcer:ct10:cvrNone:
dmi.product.name: TravelMate 8371
dmi.product.version: V1.11
dmi.sys.vendor: Acer

[Mansour Behabadi (oxplot)]

I confirm this on my Travelmate 8371G. However, I constantly get over 5 hours of battery life. Without the module, <2 hours on Switchable mode and ~3 hours on Discrete mode with Powerplay option of ATI proprietary driver.

[Albert Vilella (avilella)]

You can possibly use the code from asus_nvidia.c in the link below that has resume from hibernation support for the Asus UL30Vt/UL50V/UL80V:

http://linux-hybrid-graphics.blogspot.com/2009/12/solution-to-switch-off-nvidia-card-in.html

[Albert Vilella (avilella)]

For those with "G" Timeline models (with discrete ATI card),

David Airlie has posted v11 of his vga-switcheroo patch:
http://people.freedesktop.org/~airlied/vgaswitcheroo/0001-vga_switcheroo-initial-implementation-v11.patch

You can use the excellent howto here:
http://asusm51ta-with-linux.blogspot.com/

[Sunny (wickedsunny-3)]

I have an ATI graphics and integrated Intel graphics and the modes under windows is determined by the powered mode. I can not boot into linux from a live cd as i can not see the desktop. The welcome sound is heard but there is no graphics. All I can see is a black screen. My laptop is a HP Pavilion DV6-3006TX.

[Tuukka Hastrup (tuukkah)]

Now in Maverick, vga_switcheroo is enabled, but the extra GPU is still powered on by default.

As a workaround, I've added the following line to /etc/rc.local:

  echo "OFF" > /sys/kernel/debug/vgaswitcheroo/switch

[Adam Niedling (krychek)]

Why is this not a duplicate of bug #312756 ?

[Tuukka Hastrup (tuukkah)]

Adam, wrt bug #312756 "support graphics card hot switch":

Here in bug #435906, I'm not asking for hot switch -- what we urgently need is just that the extra GPU be turned off. I consider this a significant bug as these laptops are certainly not designed to power two GPUs at a time. Further, this is not something very complicated so I would've hoped for a fix earlier. It's even easier now that it's a one-liner :-)

[Adam Niedling (krychek)]

If it would be possible to switch between graphics cards then consequently it would also be possible to turn off the one you don't need. It seems like there is a lot of effort being made for the master bug, I don't think another project will start just for this one as this is just a subset of the main project.
What makes you think this is just a one-liner? There are many different laptops with many different graphics cards.

[Brad Figg (brad-figg)]

This bug was filed against a series that is no longer supported and so is being marked as Won't Fix. If this issue still exists in a supported series, please file a new bug.

This change has been made by an automated script, maintained by the Ubuntu Kernel Team.