Please reopen. This happens to me for Ubuntu 14.04 on a Lenovo T530 with nvidia drivers. It only happens when I switch to Discrete Graphics in the BIOS, but running in Optimus breaks other things (cannot change the virtual layout of external screens without glitches).
Using all the proposed kernel parameters in this thread so far as well as adding the EnableBrightnessControl line only prevents freezing the system, but the brightness does not change. I also tried xbacklight and changing the value in /sys/class/brightness/.../brightness. -- 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/776999 Title: [Lenovo W520] laptop freezes on ACPI-related actions Status in “linux” package in Ubuntu: Won't Fix Bug description: Binary package hint: gnome-power-manager I got the latest Ubuntu installed on a Lenovo W520 with graphics set to Nvidia discrete card. The laptop freezes, however, on power- management actions, such as brightness change and sleep/wake-up. A particularly annoying problem is that the machine freezes automatically after a GUI login if I had started gnome-power-manager previously. I have to remove the gnome-power-manager settings directory in order to get back in. If I boot with acpi=off parameter to the kernel things work fine, but then again no ACPI functionality is available. ProblemType: Bug DistroRelease: Ubuntu 11.04 Package: gnome-power-manager 2.32.0-2ubuntu2 ProcVersionSignature: Ubuntu 2.6.38-8.42-generic 2.6.38.2 Uname: Linux 2.6.38-8-generic x86_64 NonfreeKernelModules: nvidia Architecture: amd64 Date: Wed May 4 13:09:50 2011 EcryptfsInUse: Yes GnomeSessionIdleInhibited: No GnomeSessionInhibitors: None GnomeSessionSuspendInhibited: No InstallationMedia: Ubuntu 11.04 "Natty Narwhal" - Release amd64 (20110427.1) MachineType: LENOVO 427638U ProcEnviron: LANGUAGE=en_US:en LANG=en_US.UTF-8 SHELL=/bin/bash ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-2.6.38-8-generic root=UUID=df7a5cd8-18b4-4b7a-92c8-6cc8f3647cc9 ro quiet splash vt.handoff=7 SourcePackage: gnome-power-manager UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 03/02/2011 dmi.bios.vendor: LENOVO dmi.bios.version: 8BET30WW (1.06 ) dmi.board.asset.tag: Not Available dmi.board.name: 427638U 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:bvr8BET30WW(1.06):bd03/02/2011:svnLENOVO:pn427638U:pvrThinkPadW520:rvnLENOVO:rn427638U:rvrNotAvailable:cvnLENOVO:ct10:cvrNotAvailable: dmi.product.name: 427638U dmi.product.version: ThinkPad W520 dmi.sys.vendor: LENOVO To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/776999/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : [email protected] Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
