Created attachment 137006 [details]
Errors while playing CS:GO, crash and reboot after opening VLC

Another crash pretty much right after the one from my previous comment. After
rebooting the system to continue playing Counter-Strike: Global Offensive the
errors kept coming, though the system did not freeze (note the timestamps in
the error log).

After shutting down the game, I started VLC to watch a stream and the system
froze immediately. After a short while (<5 minutes) I used Magic SysReq keys to
reboot the system safely, which can also be seen in the log.

A possibly important detail: My system doesn't freeze entirely, only the
graphics output does. Sound still works for a time, even voice chatting
continues to work. However, all X output freezes (e.g. conky on desktop).

I haven't tried going to a virtual console, so do not know whether that still
works.

I also had the same issue while playing Euro Truck Simulator 2, but it never
happened while playing Dota 2. Given this, it seems like some illegal
instruction is passed to the graphics driver. Would an ApiTrace help? If so, I
can try to record one.