Computer started freezing when i dont do anything for 2 min

[JEDI]

this started a couple of days ago.

i dont do anything for ~2 min (ie: just reading an article or walk away to use the bathroom) and the computer freezes. mouse doesnt move, kybd doesnt respond, off button doesnt work. this happens about 1 out of every 2 times that nothing is going on. But it doesnt happen when i'm d/l stuff in the background.

i have to unlpug the computer to shut down. when it starts back up again, it doesnt go thru chkdsk like it usually does when i dont shut down properly.

adaware says no spyware. norton antivirus says no viruses.

Any ideas?

THX!

edit:
Nothing has changed the past 2 months. i havent installed anything, and i live alone.

 

[Cdeck]

most likely malware. what i would do is run MSCONFIG, uncheck all startups, click service tab, check hide ms services and uncheck the rest. reboot.

if it reoccurs, go to sysinternals.com and download their rootkit tool.

if it still occurs then get your data off the drive, repartition and reinstall xp. this time get an image of the clean install so the next time will save you many wasted hours.