Comment 3 for bug 791900

Well. I sincerely apologise.
I *was* on nouveau and I saw this behaviour.

I used gstreamer-properties under nvidia and thought I saw an ok test screen, but I must have screwed up somehow? 'cause now I'm back to blackness in nvidia as well.

The only thing I can think of is it is related to suspend on closed lid, which seems to occasionally muddle brightness.

I'm going to reboot now, and see if I still get a black screen on vids.

At this instant though, it appears the behaviour is the same regardless of whether I am using nouveau or nvidia.