The black screen after display rotation could be bug 1410238, which is fixed in Trusty's xserver-xorg-video-intel 2:2.99.910-0ubuntu1.4. This bug is also fixed on Utopic and Vivid.
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1326257 Title: [nvidia-prime] Cannot adjust brightness in guest session and results in black screen while changing the resolution To manage notifications about this bug go to: https://bugs.launchpad.net/hwe-next/+bug/1326257/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs