Something odd

Hi. Im new to the forums here.
I searched for a simular problem with no luck so I need to post it.

Ok , here goes. I think I'm crazy

I installed prey no problems. It plays no problems except for one. I get this weird high pitch noise from my case. It almost sounds like the motherboard speaker making it. It doesnt make this sound except when I play prey. Its not constant, but irregular. Ive tried both the higher and lower quality sounds settings with no change.
I play many other system demanding games with no such problems.
I installed the latest drivers for both my audio and video, and directx after them.
I know its the not the newest system by far, but It seems to hold up pretty well.
The case was also opened up not but a few weeks back to clean out any dust/etc.


abit IC7
P4 3.2
audigy z2 gamer
2 SATA hd's 160g each
Nvidia GeForce 7800 GS

Is it possible the motherboard speaker is making this sound? And why.
Its not like an error beep at all. A high pitch squeal that only occurs running prey.
Thanks for reading.

[superevilcube]

It kind of sounds like the motherboard speaker. I know when I was putting my computer together last week I didn't properly attach the heat sink and my MB speaker made a really loud high pitch squeal.

I don't know why your's is doing it, but it does sound like it's the MB speaker. I'm not expert by any means though =|