On Wed, 19 Dec 2018 14:22:03 -0600, Char Jackson
wrote:

I just got off the phone with a technical guy from ASRock in California.
He says the default setting of Auto for VCore should absolutely work. If
it didn't, he says they'd have gotten a flood of calls and they haven't.
He strongly suggested that I not set a fixed VCore value, since that
voltage is intended to rise or fall, as needed, rising for performance
and falling to reduce heat.

At idle, he says 0.80v is common, and the voltage should ramp up, as
needed, but the CPU has to tell the motherboard what it needs. If not,
the motherboard just happily keeps the voltage at idle, which is fine
for the UEFI screens but too low for actual booting. I typically see
0.96v to 0.97v at idle. I lose visibility during boot attempts, but I
assume the voltage is not ramping up like it should.

When I explained the symptoms, he said I should RMA the board. When I
told him this is the second board with this identical behavior, he said
it's probably the CPU. So off I go to Newegg to see if they'll be as
nice about an RMA for the CPU as they were for the motherboard.

Just finished a nice online chat with Intel tech support. After some
back and forth, he says he doesn't think it's the CPU but he agrees that
I should try to RMA it, just in case. Next stop, Newegg.