Same thing would happen to me. It would start around the 5min mark. FPS would drop to 1-2fps then stay there.
I rolled back my nvidia driver to one a couple months old, added the launch code "-malloc=tbb4malloc_bi" and started the game. Everything worked fine, then updated to the new nvidia driver and it is still working great.
ever since the big GB update yesterday my crosshairs now move independently of my body. I can face forward and move my weapon left and right without my body also moving left and right. Follow?
Kind of like how all FPS games are. Now its not like that.
I have the same problem since the new update. After 5min of play frames drop to 1-2fps and sometimes crashes right after with ACCESS VIOLATION.
Tried verifying, reinstalling, and rolling back drivers. Nothing works.
I7, 16gb, 970M