Verified with 14.04 stock image on this system again (in both UEFI / legacy mode), just like what Edward commented in comment #12, it dims slowly with both of the Intel and nVidia GPU. Therefore I will mark this bug as Invalid. Thanks!
** Changed in: hwe-next/trusty Status: New => Invalid ** Changed in: linux (Ubuntu) Status: Confirmed => Invalid -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1333638 Title: [Dell Vostro 5470] Unable to control brightness with the Intel GPU / nVidia GPU + proprietary driver To manage notifications about this bug go to: https://bugs.launchpad.net/hwe-next/+bug/1333638/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs