Random Restarts

Hello, I just built the PC and it was running perfect for about 2 weeks. Then i got a Pop and the nasty smell of the PSU dying. SO i went out to bestbuy and the only thing they had was a Rocketfish 700watt PSU. so i get everything installed again. and it worked for about 5 minutes and then instantly restarts. no BSOD was visable. and im pretty sure i dont have bios set to auto restart after BSOD. It just restarted itself, sometimes it can go 2 hours, sometimes 5 minutes. Temps seem fine. here are my specs

ASUS P6T LGA 1366 Intel X58 -
Intel Core i7 920 Nehalem 2.66GHz -
EVGA GTX275 PCIe x16 -
G.SKILL 6GB (3 x 2GB) 240-Pin DDR3 SDRAM DDR3 1333 -
DVD/RW drive -
1x 250gb HD -
1x 500gb HD -
Rocketfish 700watt PSU -
Windows Vista 64bit

I think its either a faulty PSU, or when the first PSU went it took something else out with it. Any ideas?


also NO overclocking has been done to anything in the system. Everything was at stock speeds and timings