Question Can anyone identify the problem of this PSU noise?

[Falx]

Hi,

Yesterday my old Corsair H650W started making an electrical sounding fan spinup noise at random times (at least that is what is sounds like). This happened when the system was under load or idle, it did not matter. Since the PSU had no semi-passive mode, so this is weird. It was an old unit (from around 2008-2009) so I decided to replace it.

Just installed my new Antec High Current Gamer Gold 650W and the noise is still there. If I listen closeby it does come from the PSU.

You can hear the sound here:

View: https://youtu.be/577WnxEHpeQ
(put the volume up high). It sometimes happens 2-3 times in a row, only to be silent for some minutes, then it comes back.
I already tried disabling C1E state and EIST in bios, but it does not seem to help.

Has anyone got any idea what I'm dealing with? And how to fix this pleaese?

 

[Diddly]

Have you taken the side of the case off and look for any fans spinning up when this noise occurs?

 

[Falx]

Yes, nothing that correlates with the noise. All fans are spinning at a constant rate while it happens. If I put the new PSU unit in semi-passive mode or not, it changes nothing.

 

[Falx]

I've now disabled C6 state and enabled BLCK Spread Spectrum (against electromagnetic interference). So far the noise is gone...