Windows restart

[electr.eel]

Hello...
I have a problem and i don't know why it happens.
Windows xp system restart sometimes automatically and saw me for 1 sec blue screen.
I have change the power supply, ram, vga and ethernet, but nothing.
Anybody help me?

 

[PC eye]

That is more likely a problem with Windows itself if no virus or spyware is found unless the cpu is overheating. Do you have something to monitor system temps with to see there's a problem there? SpeedFan is a free program you can download from http://www.majorgeeks.com/download337.html