Wierd Noise when running Prime95

When I run Prime95 on my Dimension 8300, there is a very high pitched, almost like a chirping sound, coming from somewhere in the Tower. I can't tell where, but it's really very annoying. It happens too when I am scrolling through documents/webpages. Any idea what it could be?

EDIT: I was thinking about what it sounded like, and it sounds like crickets, only high pitched.

Message Edited by CatoftheNight on 03-09-2004 02:03 PM