https://bugs.freedesktop.org/show_bug.cgi?id=81644
--- Comment #47 from arnej ajanbu@gmx.de --- Created attachment 104430 --> https://bugs.freedesktop.org/attachment.cgi?id=104430&action=edit dmesg
I also have these problems. I attached my dmesg.
Until now (mesa 10.2.5), my system always hung completely and I had to reboot. Now I'm using mesa git and the screen goes blank, sound continues from the youtube video, and after about 10 seconds the screen is back and usable again.