Hi, i just got my EVGA GTX580, i plugged in. pc starts normal. then downloading the latest drivers, installing. after rebooting i`m trying to login and then pc restarts. then i need to run on safe mode, if i run in normal mode pc restart. tried few version of drivers. Motherboard is GIGABYTE EX58-UD5 and with HD5970 Radeon no problem. Need help. Anybody had this problem?