I just ran enough tests to maximize the load on all CPU cores for my i7. It sounds like your system is definitely more stable graphics-wise than mine is.
I was playing CS again on Friday night and I got several segfaults, and only AFTER the segfaults did I get driver crashes (xid errors). I spent a little time this morning looking at a couple of them in gdb. I’m unfamiliar with Ubuntu, so I won’t be able to guide you step-by-step, especially since Ubuntu isn’t on systemd.
You’ll have to find where Ubuntu puts the coredump files, make sure gdb is installed, then run
gdb nameofcoredumpfile
Now enter these commands at the gdb prompt:
(gdb) set logging on
(gdb) bt full
# you might have to press enter a few times until you get the prompt back
(gdb) quit
and you’ll get a gdb.txt file in your current working directory.
My two most recent crashes appear to have originated in libtier0_client.so, which is a CS GO library. Here are my gdb coredump backtraces:
http://sprunge.us/BPDP
http://sprunge.us/BNbV
These definitely seem like pure CS:GO bugs to me, though I don’t know exactly what that library is… I must be having multiple issues here, considering the fact that my system isn’t stable while running some OpenGL stress tests even.
Anyway, maybe check your coredumps and see if there’s anything similar there for you, and we could probably bring some of that info back to Valve’s issues system.
If anybody has any information on how I can get to the bottom of my graphics instability issue, please let me know.