Question New ASRock Z390M-ITX/ac + i9-9900K build - absolutely unbearable and insane coil whine

[Archon810]

All of a sudden, about a day after I built a new mini-ITX rig, I'm getting absolutely insane coil whine, even at idle.

Here's a video showing the whine that just started all of a sudden:

View: https://www.youtube.com/watch?v=PIcUIk0nvNE
.

Here's one from about an hour prior when I was running some benchmarks:

View: https://www.youtube.com/watch?v=M8Xbs7eYyOc
.

Here's the full list of parts I just used for this build https://pcpartpicker.com/user/archon810/saved/vJfNQ7.

What the heck? Since there's no video card (I picked this board specifically because it was the only one with 3 modern video outs - 2 HDMI + 1 DP - in mini-ITX size), it has to be the ASRock motherboard, right? It's unbearable.

It's gone now after a reboot, but for how long...

I saw suggestions to disable C states, but that doesn't make sense to me. Once the loud whine started, it didn't stop until I rebooted - whether idle or when running a benchmark. If it were related to some C states, surely starting/stopping a benchmark or loading up the CPU would change the whine.

Any thoughts?

Thanks!

 

[Archon810]

As I mentioned, I just restarted, and the noise is gone (only a faint one present when I open the case and get my ear inside). The one in the video before that was unbearable with a closed case across the room.

I know it's going to come back, but what is causing it?

I'm running the same stress test now after the restart, and the loud chirping noise I was hearing in the 2nd video (the benchmarking one) is gone too.

I'm so confused.

 

[vistascape]

i have an asrock z390m pro4 which is making coil-whine. specially when playing game. i7 9700k.

how can i fix this?

 

[ocer9999]

Strange, do you have the back of the case fan always off?
The motherboard, that one in particular needs a decent airflow on the VRMs, considering you have a 9900K, that's a lot of juice.

 

[Archon810]

I've been running this setup for over a month now, and I'm glad to report that the whine hasn't come back at all. It's been a real dream PC. Still no idea what happened there.