Having Serious Problems - Constant reboot

[toprock03]

Good Morning -

I built my first pc about a year and a half ago with no issues whatsoever. Now all of the sudden my computer keeps randomly rebooting. Sometimes I'll be using windows for a half hour or so with no issues until a reboot, and other times it will get itself into a cycle where it will reboot, not even finish loading the bios, and then reboot again.

I took the computer to a PC place where they did a diagnostic. They "claimed" they swapped the parts and it was either the MOBO or the CPU. Figuring the failure rate on the MOBO was much higher than the CPU I RMA'd the MOBO. After weeks of waiting and finally slapping it all back together I am seeing the same issue.

I dont think its a heat issue as I installed speedfan and temps seem to be very stable and operated usually between 50-60c when under load for all areas. I am obviously sick of the problem and dont know what to do. I could RMA the CPU but if thats not the issue its another 2 weeks and no progress. Could it be a bad power supply? I wonder if the PC place (pretty reputable within the milwaukee area) did a lazy job of actually trying to solve the problem. I dont think its a windows issue as it will sometimes reboot before even loading vista

Any help is greatly appreciated. Thanks in advance for all replys

ENCORE ENLWI-N PCI 2.3 Wireless Adapter

LG 22X DVD±R DVD Burner Black SATA Model GH22NS30 - OEM

Arctic Silver Ceramique Thermal Compound - OEM

Western Digital Caviar Black WD6401AALS 640GB 7200 RPM SATA

G.SKILL 6GB (3 x 2GB) 240-Pin DDR3 SDRAM DDR3 1333 (PC3 10666)

ASUS P6T LGA 1366 Intel X58 ATX Intel Motherboard

SAPPHIRE 100259-1GL Radeon HD 4870 1GB 256-bit GDDR5 PCI

Microsoft Windows Vista Home Premium SP1 64-bit for System Builders -

Intel Core i7-920 Bloomfield 2.66GHz LGA 1366 130W Quad-Core

PC Power and Cooling S75CF 750W EPS12V SLI Certified CrossFire Ready 80 PLUS Certified Active PFC Power Supply

 

[broncos78254]

I have had similar problems with some of my builds in the past as well. In my experience, these problems were usually the result of either bad viruses and worms/trojans etc. or PSU problems. I'll take it for granted that you have already checked and double checked for viruses, so I would guess that your problem may perhaps be the psu. PC Power and Cooling is a reputable brand however. But it does sound like a psu problem. How old is your psu? The ram could also be the problem, so be sure to run a ram check, just to make sure that they're still running well. Hope this helps.