High pitched sound at seemingly random times Options

[Hintswen]

My computer has been making a high pitched sound at what seems to be random times. It's a long sound and can sometimes last for hours. It hasn't happened any time I have been in a position to take off the side of my care and try and hear what it is coming from though.

It would most likely be the power supply right?

[Hintswen]

Intel Core2 Quad Q9650
6GB RAM
NVIDIA GeForce GTS 250

Also have a old Leadtek DTV1000T in there.

No idea exactly what the "PSU" is.

It actually hasn't happened for quite awhile.

[R4N]

Intel Core2 Quad Q9650
6GB RAM
NVIDIA GeForce GTS 250

Also have a old Leadtek DTV1000T in there.

No idea exactly what the "PSU" is.

It actually hasn't happened for quite awhile.

WAAAAAAAAAAY overpowered for any shaw, even a 1500w.
The problem with shaw or any generic power supply is their advertised wattage is nowhere near their actual capacity.
I have read somewhere that someone tested a 1500w shaw psu with a PSU tester, and it crapped out at about 280w.

This would be the source of your issues, overworked power supplies tend to squeel.
I am amazed the machine is even functioning

I recommend forking out about $90-100 on your new Power supply.