high-pitched noise during bootup

[Carl-Daniel Hailfinger]

Hi,

I have noticed some high-pitched noise during each bootup,
estimated frequency is >12kHz. Sounds like a bird chirping,
but with a much higher pitch near the upper hearing range.
The sound is also quite quiet and can't be heard if any
fans of other machines are running.

Could anybody verify my findings in a quiet room without
air conditioning and other sources of noise? This sound
gives me a headache and at least one other person can
hear it, too.

I would record it if my microphone wasn't so crappy.

Regards,
Carl-Daniel