What would make my computer make a screeching sound when only playing a certein game?

[Compddd]

I can play UT2004, BF1942, C&C Generals, but when I load up Asherons Call, something inside my computer starts making a screeching sound. I am dumbfounded, I stopped all my fans to see if it would go away but even after there all stopped it keeps screeching, but if I alt tab out of the game, the screeching stops, as soon as alt tab back in, screeching sound comes right back. All my speakers are disconnted too and it still does it. Only on Asherons Call, I am dumbfounded. =/

 

[volrath]

Is it coming from your monitor or your actual computer? My monitor screeches at certain resolutions and refresh rates.

 

[Compddd]

I think its my Pos 9800XT fan afterall, I played UT2004 for 30 mins so the XT's fan would get reved up into high mode, went into Asherons Call, no screeching, I think its screeching at low fan mode on the XT since Asherons Call is a 5 year old game and doesnt really tax the system enough to warrent the XT jumping into overdrive fan mode. Bring on R420 please!