Dell E7440, same problem on 14.04: very quick to change brightness using intel_backlight command, but hardward keys (Fn-Up/Down) pause the computer briefly.
Thanks to instruction from user Toz (http://ubuntuforums.org/showthread.php?t=2208278), the fix requires both "acpi_backlight=vendor" kernel param and creating the /usr/share/X11/xorg.conf.d/20-intel.conf file: ------------------- Section "Device" Identifier "card0" Driver "intel" Option "Backlight" "intel_backlight" BusID "PCI:0:2:0" EndSection ------------------- -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/847001 Title: Adjusting display brightness is very slow on several Dell laptops To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gnome-power-manager/+bug/847001/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
