我部電腦死機

I'm Alvin. I'm happy to answer your question.

I think your computer didn't have enough speed or your computer have virus. You can download the free anti-virus software like NOD32, McAfee, avast! or some more (but I think avast! is better) and use it to scan your computer.

If virus found, please delete it.

If you can't find the virus, you may download another better anti-virus software to scan your computer again.

If your computer can't find virus, please press F8 before your screen shows Windows to go to the safe mode or you may buy a faster RAM.

If you use the faster RAM and Windows shows BSOD or RSOD, please use the old one.

If the problem continue, please contact some IT to help you.