Ok, so a friend's laptop gets very hot, very quickly, then just cuts out dead, the fan seems to be working and it's never under any sort of excessive load. Frankly, I'm a bit stumped.
I'm pretty sure that it's the CPU, but I'm not sure why. I was thinking open it up, clean the insides and re-seat the heat-sink with new thermal compound.
I have a week until I next have a chance to look at it but some ideas would be helpful in case this is stupid/doesn't work.
Also, while I'm here, the same laptop drops the connection to two different wireless routers, frequently and at random intervals. I'm going to be performing a re-format and fresh windows 7 install with the newest drivers of course and failing that I have a spare wi-fi card to replace the old one with. Is there anything I've missed with regards to this, bearing in mind that I've ruled out both routers as potential causes.