Unfortunately, I no longer have this device - it was stolen. I may be able to get my hands on such a device to try it, but that is a long shot. If reproducing on an updated T420 is required to continue working on this bug, then I suggest to close it for now and if I manage to reproduce I'll reopen.
-- You received this bug notification because you are a member of Desktop Packages, which is subscribed to xorg in Ubuntu. https://bugs.launchpad.net/bugs/1306470 Title: Under KDE, X consumes 100% CPU after returning from VT switch Status in xorg package in Ubuntu: Incomplete Bug description: Running on current trusty (though is has been going on for a while), when I'm using KDE and I switch to another VT, when I get back into KDE the X server is eating up all the CPU (of one core). After a few minutes it settles down. Also, while the CPU is loaded, sometimes (not always but most times), my keyboard is not responding, and the desktop behaves as if one of the keyboard switch states is stuck - for example usually it looks like the ALT key is stuck and when I try to click on windows with the mouse, I get the move window behavior, as if I'm holding the ALT key. The behavior of CPU load is 100% reproduceable under KDE when doing a VT switch. It never happens when I use XFCE or GNOME shell (I wanted to try unity, but I'm having problems installing it). Also, it often happens when I get back from sleep to KDE (not 100% though). ProblemType: Bug DistroRelease: Ubuntu 14.04 Package: xorg 1:7.7+1ubuntu8 ProcVersionSignature: Ubuntu 3.13.0-23.45-generic 3.13.8 Uname: Linux 3.13.0-23-generic x86_64 ApportVersion: 2.14.1-0ubuntu1 Architecture: amd64 CompizPlugins: [core,bailer,detection,composite,opengl,compiztoolbox,decor,snap,gnomecompat,mousepoll,vpswitch,resize,move,imgpng,grid,regex,wall,place,unitymtgrabhandles,session,animation,fade,expo,scale,ezoom,workarounds,unityshell] CompositorRunning: kwin CurrentDesktop: KDE Date: Fri Apr 11 11:48:56 2014 DistUpgraded: 2014-01-13 15:03:26,904 DEBUG enabling apt cron job DistroCodename: trusty DistroVariant: kubuntu GraphicsCard: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller [8086:0126] (rev 09) (prog-if 00 [VGA controller]) Subsystem: Lenovo Device [17aa:21d0] NVIDIA Corporation GF119M [Quadro NVS 4200M] [10de:1057] (rev ff) (prog-if ff) InstallationDate: Installed on 2012-11-23 (503 days ago) InstallationMedia: Ubuntu 12.10 "Quantal Quetzal" - Release amd64 (20121017.5) MachineType: LENOVO 41786VU ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.13.0-23-generic root=UUID=5bf3afd6-270a-43b7-8cd3-d1355202e6da ro quiet splash vt.handoff=7 SourcePackage: xorg UpgradeStatus: Upgraded to trusty on 2014-01-13 (87 days ago) dmi.bios.date: 03/26/2012 dmi.bios.vendor: LENOVO dmi.bios.version: 83ET69WW (1.39 ) dmi.board.asset.tag: Not Available dmi.board.name: 41786VU dmi.board.vendor: LENOVO dmi.board.version: Not Available dmi.chassis.asset.tag: No Asset Information dmi.chassis.type: 10 dmi.chassis.vendor: LENOVO dmi.chassis.version: Not Available dmi.modalias: dmi:bvnLENOVO:bvr83ET69WW(1.39):bd03/26/2012:svnLENOVO:pn41786VU:pvrThinkPadT420:rvnLENOVO:rn41786VU:rvrNotAvailable:cvnLENOVO:ct10:cvrNotAvailable: dmi.product.name: 41786VU dmi.product.version: ThinkPad T420 dmi.sys.vendor: LENOVO version.compiz: compiz N/A version.ia32-libs: ia32-libs N/A version.libdrm2: libdrm2 2.4.52-1 version.libgl1-mesa-dri: libgl1-mesa-dri 10.1.0-4ubuntu2 version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A version.libgl1-mesa-glx: libgl1-mesa-glx 10.1.0-4ubuntu2 version.xserver-xorg-core: xserver-xorg-core 2:1.15.0-1ubuntu7 version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.8.2-1ubuntu2 version.xserver-xorg-video-ati: xserver-xorg-video-ati N/A version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.910-0ubuntu1 version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.10-1ubuntu2 xserver.bootTime: Thu Apr 10 20:00:36 2014 xserver.configfile: default xserver.logfile: /var/log/Xorg.0.log xserver.outputs: product id 8510 vendor AUO xserver.version: 2:1.15.0-1ubuntu7 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/1306470/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp