Comment 4 for bug 1176566

I see something similar. Everything starts well but after about an hour or so if I open the dash it is unreadable with corrupted graphics. Then closing windows will sometimes leave images of themselves (some times upside down), windows corners can get corrupted as can window close icon.

Recently upgraded from 12.10 to 13.04.
System is 64 bit AMD, with a 8600GT Nvidia card, using Nouveau driver. Attempts to use Nvidia proprietary drivers result in a black screen after login in.