Ok this one is out there in the gaps in the great unknown of my computer knowledge.
Twice this week my laptop has shutdown. And I don't mean wound down and turned off, I mean, one second I'm working and the next the screen is black and the machine has stopped. No BSOD (Blue Screen of Death) just nadda, nothing, zip.
The first time I just restarted and np, it booted up and kept going it's merry way. This time it started up, loaded everything in windows that normally loads up and then came up with a fatal exception message and required to be shut down. This time it goes through the file check process at the start. Of course this all happens while I'm trying to autoguide through a shot

.
The only thing I can put it down to is my GPUSB adapter. It locked up the other night (after making sure it had engaged the dec correction first and left the correction running) and this error seemed to indicate a USB problem.
I've been running the GPUSB through a hub along with my Webcam usb connection. Has anyone else had this issue or should I just run the GPUSB straight through a USB port on my laptop.
Or am I right off the rails and it's probably something else? BTW I'm running XP (service pack 2)