Black Screen Crash of death?

I installed Windows XP SP2 on my late-2006 model Macbook Pro with the help of boot camp, but unfortunately Windows will often crash to a black screen (as if the display has shut off) and simultaneously crank the fans into overdrive. I have to do a hard reboot in order to recover. Sometimes it happens within 2 minutes of loading windows, sometimes 2 hours. This has never happened in OS X.

Any ideas as to why this is happening?

Interesting. Sounds like a driver issue to me. I assume you've installed the Boot Camp drivers and aren't using any 3rd party stuff? If so, have you ever updated the Boot Camp drivers to 2.1? Does it happen during processor or GPU intensive tasks (i.e. games).