..when flashing bios, always follow method to the T. Follow directions from manufacture. In your case, you probably flashed wrong bios and your CPU is not being recognized. I would try another CPU that is likely compatible. If it works, then flash the correct bios.
..sounds like PSU situation. Takes alot of juice to jolt everything back running again. How old is PSU? Think back, did you do anything new to pc? Install software or hardware? Update?
...this is where having a Xtra motherboard lying around helps. If you do, test the CPU and Ram on that. If everything works, then you know its the Mobo.
..take the bare mobo, lay it on cardboard. Input CPU, 1 ram stick. Connect to PSU source and connect onboard graphic to monitor. If available, if not use add on card. For power button, Jimmy an old one from old PC case. Always works for me.
.....dang, ...bignastyid, ..you know yer stuff. I was just on there a few hrs ago searching. Didn't know AM4 went that far back. That will work. Thanks a bunch. (y)
..thanks guys for tally ho. @overlord, yep I'll look into getting 1st gen Ryzen CPU somewhere for cheap. Do the flash bios myself.
...thanks again for the help. ;).. Stay Safe.