Same problem on HP 630 running up to date Ubuntu 12.04 64bit. The "acpi_backlight=vendor" workaround did not solve the problem at all.
-- You received this bug notification because you are a member of Ubuntu Desktop Bugs, which is subscribed to gnome-power-manager in 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 -- desktop-bugs mailing list desktop-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/desktop-bugs
