I also confirm that problem continue to exists for Ubuntu 14.04 using th standard Linux X1 3.13.0-30-generic #54-Ubuntu SMP Mon Jun 9 22:45:01 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux kernel.
The way around it is to go the console, adjust the brightness to desired level, then go back to X. Brightness adjustment doesn't work at all when in X. Just console after I unplug the external monitor or reboot the entire machine. -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1291371 Title: thinkpad screen dims after unplugging external display, and won't re- brighten without leaving X Status in “linux” package in Ubuntu: Triaged Bug description: When I un-plug the external VGA cable from my Thinkpad X200s, the screen dims. Hitting Fn-Home (the brightness-increase key) does nothing. Suspending and resuming doesn't reset this, though a reboot will allow me to use the brightness controls again while in the POST and after. My current workaround is that every time I disconnect the monitor, I have to C-M-F1 to get to a virtual console, brighten the screen, and then M-left to get back to X. ProblemType: Bug DistroRelease: Ubuntu 14.04 Package: compiz 1:0.9.11+14.04.20140310-0ubuntu1 ProcVersionSignature: Ubuntu 3.13.0-17.37-generic 3.13.6 Uname: Linux 3.13.0-17-generic x86_64 .tmp.unity.support.test.0: ApportVersion: 2.13.3-0ubuntu1 Architecture: amd64 CompizPlugins: [core,bailer,detection,composite,opengl,decor,snap,gnomecompat,grid,regex,mousepoll,compiztoolbox,resize,move,wall,animation,vpswitch,place,imgpng,workarounds,expo,fade,ezoom,session,scale,unityshell] CompositorRunning: compiz CompositorUnredirectDriverBlacklist: '(nouveau|Intel).*Mesa 8.0' CompositorUnredirectFSW: true CurrentDesktop: Unity Date: Wed Mar 12 13:22:01 2014 DistUpgraded: 2014-02-25 19:06:30,487 DEBUG enabling apt cron job DistroCodename: trusty DistroVariant: ubuntu EcryptfsInUse: Yes GraphicsCard: Intel Corporation Mobile 4 Series Chipset Integrated Graphics Controller [8086:2a42] (rev 07) (prog-if 00 [VGA controller]) Subsystem: Lenovo Device [17aa:20e4] Subsystem: Lenovo Device [17aa:20e4] MachineType: LENOVO 7465CTO PackageArchitecture: all ProcKernelCmdLine: root=UUID=5237fceb-23d0-412d-84d9-b8f8b3bf28af ro quiet splash SourcePackage: compiz UpgradeStatus: Upgraded to trusty on 2014-02-25 (14 days ago) dmi.bios.date: 06/25/2009 dmi.bios.vendor: LENOVO dmi.bios.version: 6DET55WW (3.05 ) dmi.board.name: 7465CTO 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:bvr6DET55WW(3.05):bd06/25/2009:svnLENOVO:pn7465CTO:pvrThinkPadX200s:rvnLENOVO:rn7465CTO:rvrNotAvailable:cvnLENOVO:ct10:cvrNotAvailable: dmi.product.name: 7465CTO dmi.product.version: ThinkPad X200s dmi.sys.vendor: LENOVO version.compiz: compiz 1:0.9.11+14.04.20140310-0ubuntu1 version.ia32-libs: ia32-libs N/A version.libdrm2: libdrm2 2.4.52-1 version.libgl1-mesa-dri: libgl1-mesa-dri 10.1.0~rc3-0ubuntu3 version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A version.libgl1-mesa-glx: libgl1-mesa-glx 10.1.0~rc3-0ubuntu3 version.xserver-xorg-core: xserver-xorg-core 2:1.15.0-1ubuntu6 version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.8.2-1ubuntu2 version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:7.3.0-1ubuntu3 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: Wed Mar 12 09:07:01 2014 xserver.configfile: /etc/X11/xorg.conf xserver.errors: xserver.logfile: /var/log/Xorg.0.log xserver.outputs: product id 16404 vendor LEN xserver.version: 2:1.15.0-1ubuntu6 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1291371/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp