PC restarts with a BLUE SCREEN!!?

PC restarts with a BLUE SCREEN!!?

My old pc back home starts to cause problems. It spontaneously restarts when my sister is running any spyware remover softwares (spybot,spydoctor) or play a video, If she disables the restart option, an error occurs; A blue screen pops up saying
DRIVER_IRQL_NOT_LESS_OR_EQUAL
or
PAGE_FAULT_ON_NONPAGED_AREA

She have run extensive checks on the hard disk and memory modules, but didn't find a single error.
No new hardware installation recently.
No new drivers installation recently.

I am out of solutions....


Mircosoft Windows XP Professional
Version 2002
Service Pack 2

AMD Athlon XP 2000+
1.67 GHz, 256 MB of RAM

P/s; Dont tell me it's all about virus/trojan, i don't think it is at all. The pc runs well most of the time, only this restart crap that causes the frustration.

Solution:-Could be one of your cards is faulty. A similar problem happened to my PC before and after some extensive and time consuming trouble shooting, I found out that my video card was faulty.