CW-NAS-ADLN-K Powers Off in Bios

Oddly, I can boot an OS and it stays up for MUCH longer.

It crashed during a BIOS update, and bricked.  I purchased the CH341-A adapter and flashed the bios chip directly with the latest bios, and it is back up, but still crashing in bios settings.  Screen goes black, light flickers, and it reboots.

I am running memtest86+ now, so far no errors.  It is 20% done.

I am thinking something is wrong with power management, a bios setting, or the power supply....
However, I have tried two power supplies, and they are both doing the same thing, though the "pico" one seems more stable.

I have done obvious things, like tried removing all hardware except the minimum to boot, no NVME, no PCIE slot, etc.
I am thinking really this has to do something with bios settings and power management, or the power supply - but it is odd it stays up once an OS boots...?

The CPU temp is staying below 30C.

I keep leaning towards power supply - maybe voltages are being unsteady as the current draw is so low.  I have one more coming in....does anyone know of any that work well?  I will run memtest overnight.  If it stays up it means it's stable under heavy load but not idle load...