This is a problem for me that has been going on for an extended time. My computer will just up and go black and restart itself, and the blue screen comes up that it was not shut down properly and c/drive needs checked for consistency. I run XP PRO. anyhow it does the scan, sometimes files are found not to be valid and will be truncated mostly those come from either Firefox, or Ytunnel.

anyhow it does start, and sometiimes the window pops up to tell me system has recovdered from a serious error, and i send an error report to windows and it said an unknown driver was the most likely cause. other times i do not get the error window at all. this has been an ongoing thing, almost a year, and it continues to work fine, aside from that.

Sounds like your computor might be overheating. try taking the cover off and watch the computor boot up(dont touch anything while its doing this) make sure both your power supply fan and CPU cooling fan are working properly. if the CPU is not working turn the computor off again check that its plugged into the motherboard properly and that there is nothing clogging it and stopping it spinning.the other option might be that there is a problem with your power supply so if u were really desperate for a fix then you could try replacing that. The only other tghing it might be is if its a Dell and its over 2-3 years old then it could just be your hardware starting to fail in which case the best option would be to buy a new computor.