My new laptop computer has been making squeaking noises that only me and my cat can hear. I know I'm not insane (My sister can hear it to). It's not a loud sound, but it is annoying.

This I've already figured out: the sound is only audible when I'm online. Other then that, everything is fine. But when I logon, bam. There's my noise.

What the hell is it? I'm going insane.

I would usually think of the harddrive for a high pitched squeal. But only when online? That's a poser.

Modem or network card related maybe?

That was the first thing I checked. Everything is in normal and working order, it's just making a squeaking noise.

if you have another laptop, then swap the parts one at a time until you find the culprit

Usually when my computer squeaks, it's time to feed the little critter before getting him to run on the treadmill to power the CPU.

J/K.

It is possible that the high pitch sound can come from:
CPU fan
LCD Display
Power
Graphics card fan (if one)

It depends on if it's a permanent squeak, or an intermitant one. (Simply does it dot and dash or is it a long dash.)

If it's a long whine, and does occur until your OS has booted up, check that the laptops mic isn't generate a feedback loop with it's speakers.

Thats all I can guess for now.

i think it is quite common,which is your Lap brand?
...Sony vaio K,V series Laps have been frequently reporting such noises...

Stryder:
It squeaks, stops, squeaks some more, then stops. Basically on and off. And only when I'm online.

Also, is there a way I can cool this thing down? I'm afraid I might over-heat it.

Update.

It's actually higher pitched when I do not have the power cord plugged in. I think it might have something to do with the power or the processor.

Actually I was using a friends laptop the other day (A Dell one) it generated a high pitch when its harddrive was functioning.

This is a Dell. But it only makes the noise when I'm online (Note: When I connect to my schools LAN, it does not make this noise--but when I connect at home with a regular phone line, it does) or it's louder when the power cord is unplugged.