I began to suspect something was off when I couldn't get the 5820K stable at 4.3GHz (which is a very modest overclock), even at 1.350V (which is a completely overkill amount of voltage). I thought the board might have been undervolting by a lot, so I connected my voltmeter to the probe-it. Turns out vcore was at the stock 1.059V. Before, I'd been using adaptive mode, with 1.000 base +275 offset. I tried all sorts of things; 1.275 base +0 offset; switching to override mode instead of adaptive. FIVR faults on/off, FIVR efficiency on/off, Droop on/off, NOTHING WORKS. Voltage stays at stock, no matter what the board reports. I've tried different bios revisions, and I get the same behavior on 2.05, 2.03 and 1.15. What gives???