I thought I'd saved and exited several times, but now I go back and look and the manual range of vCore is available again but is still 1.45V through 1.7something.

Virtualization is also something you have to choose early after a flash: I can't touch it now.

So either the message about voltage problems isn't getting through, or they just think the early revisions have been replaced by now and refuse to support them properly. I'll have to call in to the folks who supplied BIOS chips before and see if they can transfer me to somebody who might help talk to the BIOS group...