I had a Hela 1200r for a hot minute and it made a similar noise. I use a smart plug with my computer to fully cut off power after shut down. In a way it’s like flipping the switch on the psu to fully cut power. I noticed the psu would make this noise when I turned the computer back on. Didn’t seem to happen if I would shutdown the computer and turn it back on without fully cutting the power at the plug, which leads me to believe the noise is from some component in the psu when it first gets loaded with electricity. I ended up returning the Hela 1200r due to it failing atx 3.0 certification. I now have a msi ai1300p and I’ve never heard it make that noise. The Hela 1200r operated fine though so I don’t think this sound is something to worry about.
Also to anyone else following earlier posts of mine in this thread. The Hela 1200r sent a new production unit to Cybenetics and it has now passed atx 3.0 certification. Apparently they had sent a pre production unit first and that’s why it failed one of the transient load tests.
Probably both use the same PCB, both are CWT production. I couldn't trust it and then returned it because I was going to use it as a rendering and workstation.
Probably youre right. Mine has cutoff mechanism inside, i can barely hear that something cutting off the power, but you cant control it.
I have ordered FSP Hydro PTM Pro 1200w atx 3.0 now, I know that FSP keeps the product controls tight, I hope I will be satisfied.