I've been been having an issue where, everyday, when I boot my Mac Pro, within the first 1/2 hour or so, it'll freeze and restart, automatically. I've been told that it could possibly be the Nvidia web drivers for my GeForce GTX 660 Graphics card. Is there a fix for this and also, is it necessary to use NVIDIA's drivers or can I just use the OS X Default Graphics Driver. I'm really at a loss here. Any help would be appreciated! Thanks!