Same here, nvidia MSI 660 ti PE. Had it on my old computer, and got a brand new computer today too, with all parts new and different except for the video card. Have tried doing the PhysX over both GPU and CPU, both have random crashes. Usually when I have enemy in scope and they drop to the floor, but also just randomly without any apparent reason. Sometimes after 5 minutes, sometimes after an hour, although usually more frequent. Started for me since the beta.

Added RPT Files to issue

Unable to reproduce it by following certain steps, but it happens _every_ time I play multiplayer (havent played single player since beta, so not sure if it happens there as well)