Random Restarts windows x64bit

[Xops]

guyz i have been facing this problem for past year goggled but couldn't solve any one who can solve please tell me
system specs
quad Core
Nvidia 9400gt
4gb ram
Intel Dg45id Motherboad
1.5 tb hardisk
Please guys help me UP ty

 

[redduc900]

Boot to Memtest86+ installed to a thumb drive, and check your RAM for errors. And which version of Windows are you running? You might also want to post the EXACT model of RAM you have, including the rated and current timings and voltage.