It varies on what server i play in when i'm in multiplayer.
It crashes almost right after i loaded them mission, sometimes right after i run into bushes in First Person, and sometimes just randomly in open areas.
Driving certain vehicles as the civilian truck, Hunter, M-ATV and this vehicle which i can't remember the name of makes my game crash.
If i'm lucky, i can play around 15 min without the game CTD's on me.