Crashing problem.....(may contain spoilers)

[jens]

In steam use the verify cache integrity function (or something along those lines).

As for performance, make sure to not set samples for ssao to more than 8-16 and not use high quality on ssao. Also do not use smooth edge. Other than that make sure all things in nvidia control panel is left as application controled and not forced. Finally make sure to not have a browser ideling in the background or anything else that could interfere.