Compaq Evo N600c - Fan not operating under windows

A work friend recently aquired an old laptop from the company. The laptop came with no drivers and a fresh copy of Windows 2000. He purchased a copy of windows XP and now the fan does not work when you reach windows.

When the laptop is first turned on the fan whirrs around quite happily until you hit windows, at which point it turns itself off.

Ive spent a long time trawling through google search results trying to find a fix. I've found countless references to linux, which dont help me and a few to bios updates. This particular model doesn't have a floppy drive and my attempt at making a cd boot disc was unsucessful. I've also found a few references to ACPI fan driver, which I havn't been able to find either.

An intersting thing to note is that when I installed speedfan, when I manually set the fan to 100% it kicks in for approximatly 1/2 a second... Flicking between 95-100% keeps the fan going, but obviously it isn't very effective - it merely shows that there is not a hardware fault in the fan itself.

Any help would be greatly appreciated.