I have a laptop of the same model. With "acpi_osi=Linux" the brightness Fn keys work but the graphical system sliders/notifications don't (which is not a very big problem for me).
Another way of changing the brightness, for those laptops that use integrated Intel graphics like this one, is using the "intel_backlight" command in the terminal. For example, "sudo intel_backlight 10" should change the brightness to around 10% (yes, sudo is required). You can use this command to set the brightness even lower than what the brightness Fn keys allow. I think this command is in the "intel-gpu-tools" package (it may already be installed) and should work even from a live CD. -- 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/1172945 Title: Acer Aspire 5742G brightness Fn keys doesn't change brightness Status in “linux” package in Ubuntu: Confirmed Bug description: On my Acer Aspire 5742G, the brightness function keys actually shows the brightness notification and changes its bar, but doesn't change the display brightness. I tried to add the acpi_backlight=vendor line on GRUB_CMDLINE_LINUX_DEFAULT variable and update grub, but it doesn't do anything. ProblemType: Bug DistroRelease: Ubuntu 13.04 Package: linux-image-3.8.0-19-generic 3.8.0-19.29 [modified: boot/vmlinuz-3.8.0-19-generic] ProcVersionSignature: Ubuntu 3.8.0-19.29-generic 3.8.8 Uname: Linux 3.8.0-19-generic x86_64 NonfreeKernelModules: wl ApportVersion: 2.9.2-0ubuntu8 Architecture: amd64 AudioDevicesInUse: Error: command ['fuser', '-v', '/dev/snd/seq', '/dev/snd/timer'] failed with exit code 1: Date: Fri Apr 26 00:26:31 2013 HibernationDevice: RESUME=UUID=6a7bba52-468e-4dee-8cf5-de71c5d262aa InstallationDate: Installed on 2013-04-25 (0 days ago) InstallationMedia: Ubuntu 13.04 "Raring Ringtail" - Release amd64 (20130424) MachineType: Acer Aspire 5742G MarkForUpload: True ProcEnviron: TERM=xterm PATH=(custom, no user) XDG_RUNTIME_DIR=<set> LANG=it_IT.UTF-8 SHELL=/bin/bash ProcFB: 0 inteldrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.8.0-19-generic root=UUID=ad2201cc-75ef-47fe-85ff-614ad2fec58e ro quiet splash acpi_backlight=vendor RelatedPackageVersions: linux-restricted-modules-3.8.0-19-generic N/A linux-backports-modules-3.8.0-19-generic N/A linux-firmware 1.106 SourcePackage: linux UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 08/13/2012 dmi.bios.vendor: Acer dmi.bios.version: V1.30 dmi.board.asset.tag: Base Board Asset Tag dmi.board.name: Aspire 5742G dmi.board.vendor: Acer dmi.board.version: V1.30 dmi.chassis.type: 10 dmi.chassis.vendor: Acer dmi.chassis.version: V1.30 dmi.modalias: dmi:bvnAcer:bvrV1.30:bd08/13/2012:svnAcer:pnAspire5742G:pvrV1.30:rvnAcer:rnAspire5742G:rvrV1.30:cvnAcer:ct10:cvrV1.30: dmi.product.name: Aspire 5742G dmi.product.version: V1.30 dmi.sys.vendor: Acer To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1172945/+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