I've got a box here with a significant issue...it'll just reboot once in a while, sometimes go for 48+ hours without doing it, or might do it seconds after boot, these as the specs

AMD XP1800 *cooler master cpu fan*
ECS K7S5A mb
512MB Crucial PC2100 DDR
Max 40gb 7200rpm hdd
plextor cd-rw
realtek nic
2 antec 80mm case fans
Geforce4 4200 vc
midtower case 300watt ps
Win XP home (no sp)
NAV 2002
Office 2000 Pro

It will once in a while spontaneously reboot, in any app, or doing absolutely nothing. Sometimes it will run for hours and hours and nothing unusual will occur. And sometimes it'll boot, and you fire up an app and..bam...reboot.

Have run TroubleShooter on it for hours, BurnIn for hours, MemTest passes, all the HW tests out fine. Nothing unusual in software at startup. AV definitions up to date and scanned.

We have replaced the Allied PS with a nice Enlight 300watt ps, just in case. CPU temp is within AMD spec at idle and 100% load, cpu passes all tests, case fan rps steady, Geforce monitor is all in the green. We even tried having on another surge protector and then on a known good UPS! and I'm at wits end here, and the drink machine is out of 'Dew!! Any ideas? suggestions? please help!

**only thing i've run into out on some sites was some mention of Norton 2002 not getting along in some cases with WinXP, and sudden reboots were mentioned, anyone else experience anything like that?**

I'm about ready to throw the fsuking box in the compactor...