My PC is very susceptable to psychic phenomenum as well as water
. The amount of times my rig has been 'bedevilled' then worked fine afterwards of its own accord is beyond me, damn gremlins!
. You'd think they'd find something more interesting to do by now!
...
The hair dryer fix is a good one, also the airing cupboard works well. Just make sure the mobo gets nice and warm so it drys out the underside of the socket and northbridge type chips (which have a gap under them and lots of exposed legs). I found flushing them out with isopropal alcohol (squirt it under with a syringe that's had the point filed/sanded down) works wonders as well
. Dust/dirt can cause simular problems in my experience, especialy with graphics cards...