Desert Rat UK

I had the same problem but mine sometimes occured as soon as windows started up. I got a blue screen with that annoying IRQL message. The problem is likely nothing to do with your hardware and most probably a driver issue, mine came from a driver which was signed by windows (Creative Audigy 2) and was solved with an update. Just have a look in "System Information" and see what IRQs are being shared. However, I've just installed XP SP2 and am now getting the same screen - phoned up my PC helpline and they said that it was a common issue with Sound Blasters, oh well, back to SP1 until they can be bothered to make a driver that actually works. PS. I discovered what piece of hardware was the cause by taking out all of my PCI cards and reinserting them till I got the blue screen.