Just built a dream AM5 pc with new parts I've been collecting for quite some time (transferred only gpu from old pc). As I plugged and triple checked everything and powered the ASRock SL-850G psu, the power button did nothing and constant faint beep is heared from psu as long as it is switched on. Nothing indicates that any power is going to motherboard (Asus TUF B850M).
To troubleshoot if psu was faulty I pulled crappy old Deepcool psu from the old system and put the ASRock one in. It powered on just fine (well as fine as just mobo, cpu and ram can power on).
Now to rule out power supply issue, I tried old psu on a new build and to my absolute surprise, the old psu started beeping in a slightly different tone with still nothing else happening.
There is absolutely nothing on the internet about beeping PSUs so you are my last hope.
One important thing that happened during installation of the motherboard is that one of the case screws head broke off and the body is stuck in case impossible to take out. I read somewhere that it might cause a grounding issue.
I'm guessing it is a mobo problem but what does psu beeping even mean.
Any idea would be much appreciated, thanks.