We discussed our firmware problem on the software page, if only to say that recovering from bad overclocking settings is easier to do from software. But part of the problem was that we are testing this board with old firmware.
The firmware shipping with current Z77H2-AX samples was developed way back in June. But that’s not the version we used. Our motherboard round-up invitation specifically states that, in order to keep things fair, we use the most recent firmware version published on each vendor's support page. This is to avoid special optimizations for review sites. This stuff does happen, folks. ECS didn’t publish its June firmware, though, and the only version found on its support page is from March. This is particularly problematic for an ECS board, because the company's infamous stuck-BIOS issues are often solved in its later firmware updates.
Giving ECS the opportunity to update its site after our deadline wouldn't have been fair to the vendors who submitted their products with official firmware versions right out of the gate.
A CPU Voltage setting of 1.150 V got us to a little over 1.2 V at idle, and changing the CPU Vdroop setting to Disable allowed voltage to climb to 1.25 V under load. This was the only way we could get to our target load voltage without running an excessively-high idle voltage.
In spite of our relatively low idle voltage, the board was still able to run our CPU at its 47 x 100 MHz setting. That’s not quite 4.7 GHz however, since the board’s actual base clock is 99.78 MHz.
We had to leave Intel's Turbo Boost technology enabled to reach a higher multiplier. But setting the ratio to 47x caused the CPU to jump from 1.6 GHz at idle to 4.7 GHz under load.
The Z77H2-AX doesn’t let you fine-tune memory from XMP mode, but the board retains previously-set timings when entering manual mode. Entering Manual mode from Auto mode makes SPD values your baseline, while entering Manual mode from XMP mode makes those timings stick as well. Because of that, we were able to start our DRAM overclocking effort without configuring primary, secondary, and tertiary controls by hand.