See bug https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1374607 Upstream (nouveau git), has made a patch for it since yesterday. I tried the commit on top of the ubuntu-utopic kernel git, and it fixes my issue. So I guess its a must-have, as it breaks HDMI and shutdown/suspend. Hope this can be cherry-picked. Thx Jean-Louis Dupond