Daily random restarts

[Thantis760]

I just recently built a new PC over the holidays and have been having this issue from the beginning. The problem begins like this - 1. I boot up it posts and loads win7 i am able to use it for about 5-15m before bam it shuts off with no error message just off.. then a few seconds later it boots back up or 2. I boot up and it will post then shut off or shuts off before it posts. At first i believed this to be a mobo issue so I RMA'd my previous one and got a new mobo same issue.. then i was led to believe it was my PSU to i tested it and its working perfectly.. now im stuck and have no idea what to try next any suggestions?

Specs-

OS- Win7 Home (64-bit)

CPU- Intel Core i7-950 Bloomfield 3.06GHz LGA 1366

RAM- CORSAIR Vengeance 4GB 240-Pin DDR3

Mobo- EVGA X58 FTW3 132-GT-E768-KR LGA 1366

Video-EVGA 01G-P3-1450-TR GeForce GTS 450

Case- COOLER MASTER HAF X RC-942-KKN1

PSU- Thermaltake TR2 W0388RU 600W

HDD- Corsair Force Series 3 CSSD-F90GB3-BK 2.5" 90GB SATA III

 

[Tmagic650]

Did you apply thermal paste between the CPU and its heat-sink? Too much paste is bad...The motherboard isn't shorting to the case? No over-clocking? Reset the bios to failsafe defaults...

 

[Thantis760]

yes i have paste on there its not a ton about the size of a penny spread out. im not over-clocking and ive reset the bios as well, what do you mean by shorting to the case?

 

[Tmagic650]

Not shorting to the case? Use only standoffs in the places where there are mounting holes in the motherboard. All other standoffs are removed... or not used

 

[Thantis760]

yea thats how i have it currently set up

 

[Tmagic650]

Can you borrow another power supply to try?