Do you have any overclocking in effect? Attempting to overclock just slightly beyond what the computer can reliably handle over the course of the amount of time between when you turn it on until it restarts itself would be my first guess about what your problem is.
it hasent done this in a while. the last time it did it was today when i was reading contents on a cdr.i did have it over clocked to 337 but turned it back down in fear of breaking something. it did it before this anyway
i had thye same problem, and so did my friend with his comcrap(compaq). we nerowed the problem down to a program overloading the cache. when the the cache is full and cant take no more it restarts to reset the cache. once we got ride of the program(s). i found out that it helped alot. it didnt restart ever sence
I have a creative, it has caused my system to shutoff when I removed the CD last night, and I have seen it do a couple reboots. It could be drivers like Master Mind said. And even tho it is not OC it can be heat causing it to reboot. Thoses CD roms can cook up some nasty heat. you could try removing the side panel and see if you can get it to crash again while doing the same things that have made it crash in the past.
Does your P2 have fans on it??? If they do have they stopped?
Another thing...Altho you are not doing IT, TNproud2b was having reboots and could not figure it out. I told him it was something either drawing more power from his power supply or it was going. 2 days later his 12v pump that was running off his power supply was dead. that is just another thing to think about.
Can some one stop those voices in my head telling me to Overclock my computer!!!