It didn't happen to me again, but perhaps it was related to a particular screensaver. I'm not 100% sure it's been fixed but I'm pretty sure it has.

> Date: Tue, 13 Mar 2012 22:43:03 +0000
> From: <email address hidden>
> To: <email address hidden>
> Subject: [Bug 899303] Re: [gm45] GPU locks up for a few seconds then recovers	when using xscreensaver on random
> 
> Hi Beto,
> 
> I notice there hasn't been activity on the upstream bug.  Before I re-
> ping them, let me ask, are you still experiencing these GPU lockups with
> xscreensaver?
> 
> ** Changed in: xserver-xorg-video-intel (Ubuntu)
>        Status: Triaged => Incomplete
> 
> -- 
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/899303
> 
> Title:
>   [gm45] GPU locks up for a few seconds then recovers when using
>   xscreensaver on random
> 
> Status in X.org xf86-video-intel:
>   Confirmed
> Status in “xserver-xorg-video-intel” package in Ubuntu:
>   Incomplete
> 
> Bug description:
>   crashed after xscreensaver started
> 
>   ProblemType: Crash
>   DistroRelease: Ubuntu 12.04
>   Package: xserver-xorg-video-intel 2:2.15.901-1ubuntu3
>   ProcVersionSignature: Ubuntu 3.2.0-2.6-generic 3.2.0-rc3
>   Uname: Linux 3.2.0-2-generic i686
>   .tmp.unity.support.test.0:
>    
>   ApportVersion: 1.90-0ubuntu1
>   Architecture: i386
>   Chipset: gm45
>   CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins'
>   CompositorRunning: compiz
>   Date: Fri Dec  2 14:37:51 2011
>   DistUpgraded: Log time: 2011-07-07 16:41:03.123900
>   DistroCodename: precise
>   DistroVariant: ubuntu
>   DuplicateSignature: [gm45] GPU lockup  EIR: 0x00000010 PGTBL_ER: 0x00000001 render.IPEHR: 0x60020100 Ubuntu 12.04
>   ExecutablePath: /usr/share/apport/apport-gpu-error-intel.py
>   ExtraDebuggingInterest: Yes, whatever it takes to get this fixed in Ubuntu
>   GraphicsCard:
>    Intel Corporation Mobile 4 Series Chipset Integrated Graphics Controller [8086:2a42] (rev 07) (prog-if 00 [VGA controller])
>      Subsystem: Acer Incorporated [ALI] Device [1025:029b]
>      Subsystem: Acer Incorporated [ALI] Device [1025:029b]
>   InstallationMedia: Ubuntu-Netbook 10.04 "Lucid Lynx" - Release i386 (20100429.4)
>   InterpreterPath: /usr/bin/python2.7
>   MachineType: Acer Aspire 1410
>   ProcCmdline: /usr/bin/python /usr/share/apport/apport-gpu-error-intel.py
>   ProcEnviron:
>    
>   ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-3.2.0-2-generic root=UUID=34529bb0-121c-4f52-b1b7-6aca0f1c8e88 ro splash vga=789 quiet splash vt.handoff=7
>   RelatedPackageVersions:
>    xserver-xorg             1:7.6+7ubuntu7
>    libdrm2                  2.4.27-1ubuntu1
>    xserver-xorg-video-intel 2:2.15.901-1ubuntu3
>   SourcePackage: xserver-xorg-video-intel
>   Title: [gm45] False GPU lockup  EIR: 0x00000010 PGTBL_ER: 0x00000001 render.IPEHR: 0x60020100
>   UpgradeStatus: Upgraded to precise on 2011-12-01 (1 days ago)
>   UserGroups:
>    
>   dmi.bios.date: 09/08/2009
>   dmi.bios.vendor: INSYDE
>   dmi.bios.version: v0.3117
>   dmi.board.asset.tag: Base Board Asset Tag
>   dmi.board.name: Base Board Product Name
>   dmi.board.vendor: Acer
>   dmi.board.version: Base Board Version
>   dmi.chassis.type: 1
>   dmi.chassis.vendor: Chassis Manufacturer
>   dmi.chassis.version: Chassis Version
>   dmi.modalias: dmi:bvnINSYDE:bvrv0.3117:bd09/08/2009:svnAcer:pnAspire1410:pvrv0.3117:rvnAcer:rnBaseBoardProductName:rvrBaseBoardVersion:cvnChassisManufacturer:ct1:cvrChassisVersion:
>   dmi.product.name: Aspire 1410
>   dmi.product.version: v0.3117
>   dmi.sys.vendor: Acer
>   version.compiz: compiz 1:0.9.6+bzr20110929-0ubuntu7
>   version.libdrm2: libdrm2 2.4.27-1ubuntu1
>   version.libgl1-mesa-dri: libgl1-mesa-dri 7.11-0ubuntu4
>   version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
>   version.libgl1-mesa-glx: libgl1-mesa-glx 7.11-0ubuntu4
>   version.xserver-xorg-core: xserver-xorg-core 2:1.10.4-1ubuntu5
>   version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.6.0-1ubuntu13
>   version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:6.14.99~git20110811.g93fc084-0ubuntu1
>   version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.15.901-1ubuntu3
>   version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:0.0.16+git20110411+8378443-1
> 
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