i always had random gamecrashes in multiplayer mode due to that physx thingie through the beta, and wonder they continue to happen in final release. its totally random to me, sometimes in menu, sometimes after loading, sometimes within the first 15 minutes, sometimes after 3 hours .. i have no clue what that happens.
to my specs:
win7 64bit, i7 870, 8 gigs of ram, ati radeon 6870 .. already tried bunch of different drivers (chipset, graphics card, direct x, etc etc etc). i also reinstalled windows .. no change..
i hope you can fix it soon, because by now the game is some sort of unplayable for me