Antec VP550P for Ryzen 5800X bad idea?

Hi

I build a PC and everything seems fine up to a Q-CODE 02 point.
I tried to run without front panel sound and USB, 1 socket is taken by AIO anyway. Tried to run it with single stick RAM. Everytime I end up in BIOS setup.
I could replace GPU with 1050 and 4+4 CPU power with 4-pin only (book say don't do it) but I think all I manage will be a waste of time... I am not even sure what "AP initialization before microcode loading" might mean.

ASUS ROG Strix x570E Gaming - (v.3201)
Ryzen 5800X
Corsair Vengeance LPX (2x16GB) 3600 MHz
1080 GTX
Antec VP550P

I've found some people with 02 error but they reported no screen and/or on-board LEDs showing problems with RAM, GPU. Thats not my case.
I started thinking perhaps I should have 8+4 PSU or at least something more modern than I have. Should I try RMA and which components?

Tried to run with 4-pin CPU power with the same results.

Out of curiosity have you tried swapping stick to every slot? IIRC the best slot for single stick operation is the furthest from cpu.

Silly question but are you on latest bios? I had to flash my board with a 3800x before 5800x would post.

As far as power supplies go I was using a PC power and cooling turbo cool 1200 up until yesterday, it's so old it has the old rear mounted 80mm delta fan in rear that is deafening....it worked fine.

I only swapped and went lower for real world and to end noise pollution.

Out of boredom I tried all RAM slots and it runs as good as before in each configuration. Replaced 1080 with 1050 and i digged out X30 magnification to find nothing interesting in these slots.

I don't know what BIOS version was present on my first run but none of my keyboards worked so its updated to 2301. Perhaps its my luck and they botched xmass release. I'll check for newer one later. Now I wonder why shop haven't respond this year...

chew* Thanks for that info on PSU.