Odd PSU problem

Had a power supply die, so I replaced it with a used one I had that I 
had marked "good."

It booted to the bios and I just set if for default but it never loaded 
the OS. It just returned to the bios.

HD was detected and set for first boot option.

Though I was sure I had a legacy Win10 install, I did try UEFI but still 
could not get past bios.


Finally a cracked open a new in the box PSU and all worked fine. I 
assume there was some low voltage.


Both sup[plies went to a metal scavenger