I have an HP Compaq xw3100 workstation, see it at:
OS: XP Professional
Everything works fine EXCEPT, as the demands on the CPU increase (as viewed in the Windows Task Manager, Performance tab) the machine starts to sound like a jet engine reving up for takeoff. It gets so loud my kids won't use the machine.
I have a nearly identical machine that does not do this.
Not certain if the sound comes from the hard drive or the fan, but I'd guess the hard drive.
Any thoughts on how to quiet it down?