I'm using a slightly overclocked GTX 560 Ti. I've stress-tested the GPU with heavy benchmarks (Furmark, 3DMark) and it's stable. Crysis 2, however, tends to freeze often. The screen just randomly goes black and the game becomes unresponsive. The background music still goes. I can Windows+L to the lock screen, but I can't Alt-F4, Ctrl+Shift+Esc, or anything to get out of the game. I have to restart.
My overclock might be causing this, but Crysis only uses about 60% of the GPU, so I don't understand why it would. It's stable with Furmark and 3DMark, and those use all of the GPU. Is this a Crysis problem? I'm running all settings on Ultra, but this has happened on Extreme as well.