Hi,

You have two very good answers there, but we do need a bit more info.

1. Does it shut down, restart or just crash?
2. Does this happen after about a minute (virus) a longer, but consistent time (heat) or is this something that happens at random/irregular times (possibly software problems, EMP, power supply, etc...........)
3. What is the operating system?
4. Has he applied all the updates?
5. Is he running a firewall?
6. What is the machine doing when this happens?

Cheers