Comment 62 for bug 762918

Happened to me again, also; I had the lid closed on the laptop and Transmission running full screen, and it was closed for perhaps
10-15 minutes. I was able to restart X with ctrl-alt-bkspace. This seems consistant with comments up thread that disabling sync_to_vblank only minimizes the occurance of the bug and is not a true work around.

I am thinking that this could be triggered by Transmission running full-screen and the screen blanking that happens when you shut the lid. Of course, this didn't happen in 9.10.