[SOLVED] New Build High Pitched Noise - HELP NEEDED!

[Novica Obadic]

Hi, yesterday I built my PC and after turning it on it started to produce high pitched noise (like a tea kettle). I have a BeQuiet Dark Base Pro 900 rev.2 case and in front of the case there is a slider that regulates normal and full speed for the fans. When this is set to full speed the high pitched noise is gone, but soon as I put it on silent/normal mode the pitch starts immediately. The case itself has a PWM controller on the side where the cable management is, so could that be a problem? I have tried to stop every fan to see if the noise will stop or if the problem is in the fans, but nope; the noise only stops when fans are set to full speed (which I don't prefer since the case is on the top of the desk next to my ear, so it's not very silent).

Full specifications are:
Intel i9-12900k
Noctua NH-D15
Asus Rog Strix Z690-e
G.Skill Ripjaws S5 64GB DDR-5 CL36 5200mhz
Samsung 980 Pro
Samsung 970 Evo Plus
Seagate Barracuda 2TB 7200 RPM
MSI RTX 3090ti GAMING TRIO 24GB
BeQuiet Dark Base Pro 900 Rev.2
Seasonic FOCUS Plus Gold 1000w
BeQuiet Silent Wings 3 (extra fan on top for exhaust)

Any advice or help appriciated, thank you!

 

[Vic 40]

Still there with the side panel off?

 

[Novica Obadic]

Still there with the side panel off?

Yes, with both side panels off. I even tried to unplug PWM hub connector from the motherboard and CPU fans from the motherboard, the issue is still there. I'll try unplugging individual fans one by one to see if I'll resolve this or not.
But it's very strange to me, as soon as I put the fan slider on the front of the case to full speed for the fans, the high pitched noise is gone.

 

[Vic 40]

I'll try unplugging individual fans one by one to see if I'll resolve this or not.

Okay let me know how that turns out.

 

[Novica Obadic]

Okay let me know how that turns out.

After disconnecting the fans individually, I noticed the noise was being reduced as I unplugged one by one. The problem was in the fan hub of the case itself. I ended up connecting all the fans directly to the motherboard (thank god it had enough connectors for that), and now everything is working quietly and without problem. Thanks for the reply and advice. Cheers!