Why does the motherboard whistle in the processor area?

Question

Iron

Gentlemen, I bought the motherboard from my hands.
No load in the area of ​​​​the processor whistle-squeak (maybe at the 12V connector). You run a stress test, it stops. Yes, it can grow and shrink on its own.
BP, it seems that it "sings" with the same frequency, although it is good and worked without squeaks-problems on the last assembly.
What can happen to her, how critical is it?

Answer 1

In general, I turned off the energy efficiency functions in the BIOS, the frequency stopped falling below 1.9 GHz (Core I5-2300 processor, overclocked by a multiplier to 4.15 GHz with turbo boost).

Answer 2

Not critical if the sound does not interfere.