sharp high noise

[Jon]

im fixing up a old computer and whenever i give the computer power it makes a ever high pitch noise i have no idea what is wrong any help would be great.

[Detox]

Old computer...high pitched noise...is it the CPU fan burning up?  Is there any odd smells?  Does the computer boot up?  Is it the hard drive burning up?

[jon]

the cpu cooler isn't hot the computer doesn't even start none of the fans or anything all i have to do is plug the system in and it makes the soud i know the case and power supply is ok cause i've used a different motherboard in it.

[Detox]

I have a monitor thats make a loud high pitched noise as well.  Maybe if we put the two together maybe they would cancel each other out.  But seriously is it coming from the little case speaker thats plugged into the board or is it one of those sounds they use for hearing tests in the booth, or one of those sounds you expect only a dog to hear?