Thought I would post a confirmation a HP as well. Dv6t QE 7000 with HD4000+GT650m Optimus and Ubuntu 12.04 x64, this same issues is noticeable from a clean install all the way to installing Bumblebee. Adjusting brightness via the brightness and lock window introduces lag only momentarily and while the brightness is actually changing. Adjusting via the laptop's keyboard has prolonged (10s?) effects on the mouse cursor and delay to the on-screen display pop-up.
-- 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