Strang squeak/squeal from PC when scrollwheel used.

[pinkaardvark]

Ok this is an odd one. I have microsoft intellimouse explorer v2 and a logitech wireless keyboard. When I scroll the mouse or use the scroll wheel on the keyboard I get a squealing noise coming from the PC. The noise isn't excessively loud ie with any audio running you wouldn't hear it but with sound off i can hear it from 2 metres away(PC is a HTPC in living room)

I only get it when i'm actually scrolling something ie a web page, not just when scrolling the wheel with no active scrollable document open.

I get this regardless of whether the PC is connected to an amp or not, in fact i'm 100% positive the noise comes directly from the computer chassis. I have experience similar noises on other PC's and I assume it's some form of elctrical interference causing either the psu or some other chip on board the mobo to create noise.

any ideas on how to cure it or at least an explanation of what is making the noise?

p.s. it also happens when you maximise or minimise a window ie same volume but not as scratchy sounding a noise as the mousewheel.

Spec

Asus A8N SLI Premium
4400x2 AMD with Arctic cooler pro 64
Coolermaster case
6600GT PCI-E
Twin Seagate 200gb sata 2 drives
Hiper 580W PSU

 

[pinkaardvark]

Well turning off the minimize/maximize window animation in XP does get rid of the noise when minimizing or maximizing however turning off smooth scroll doesn't help so far with the scroll noise.