Comment 0 for bug 435906

Some new 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, someone has found a solution that turns off the discrete GPU in the switchable mode. It's a simple kernel module called "lenovo_acpi" that calls the ACPI BIOS: http://georgia.ubuntuforums.org/showthread.php?p=7933876#post7933876

It was originally made for Lenovo U330, in that thread it's reported to work on Acer Aspire 4810TG (Timeline) and Acer Aspire 5810TG (Timeline). 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. The module doesn't re-apply the fix after resume from hibernate, so I've had to list it in the pm-utils
SUSPEND_MODULES variable.

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