High Pitched Noise from Mobo / CPU

Could be one of the fans from the CPU cooler. Easy to diagnose: stick a pencil in a fan while it's spinning to make it stop for a sec. If the noise goes away, you have a culprit.
The CPU are thermally protected nowadays, no need to worry about overheat damage.
Oh, and if the chipset is actively cooled (has a fan on it), will have to check that as well.

The noise still there. My CPU only using standard fan and the chipset doesn't have a fan on it. Do you have anything else that I could try?

Download speedfan or core temp.
Are you using stock intel cpu fan?

Yes, i'm using stock intel cpu fan and my CPU still at reasonable temp (38-41). Must I downclock my cpu using speedfan? if so, how?

It's normal for stock cpu fan to ramp up under full load.

The noise is still there now, or it was still there while the fans were blocked?
If noise still there while stopping a fan, that particular fan is not the culprit. If the noise stops while the fan is stopped, you got it.
Don't forget the fan inside the PSU and the GPU cooler, as well.

The problem isn't the fan.

Can you tell us the steps taken to ensure that NONE of the fans was the culprit?

The fan isn't the problem because I turn off every fan one at a time by unplug the power (only PSU, CPU, GPU fan I use my finger to stop it) and the noise still audible. But...

I'm very very sorry my fellow tom's hardware friends.

The real problem is "There is not enough power to supply my PSU" because
1. My PSU is 600watts
2. Because unstable voltage at my place I use voltage stabilizer to make sure the output voltage is 210~230 volt.
3. But my stupidity is I DO NOT check the capacity of my voltage stabilizer, it only supply 500 watts.
4. So I change my voltage stabilizer to 1000watt capacity and the noise is gone.

Then again I'm very very sorry...
Thank you all who already participate in my thread.
Have a nice day... Case Closed

Best answer selected by lantz44.