Core VID is always 1.250 stock. If you change that manually, it'll not bootup Meaning it must set the Amps fed to each core like you say, yep. And multiply amps by the core voltage gives you the power consumed under maximum lab load. That's where they get the TDP value from then. Very nice.

However, mine has set 1.2000VID many times randomly and that makes you get less HT reference MHz.