actually, the board was not toasted. I was able to get to bios, just not, at first, able to run more than two ram modules.
I am still not able to revert to an older bios but I no longer want to. I was able to get all four ram modules running by bumping the Vdimm to 1.25.
The new bios is, otherwise, better. Vdroop has all but disappeared and stability is great.