P9X79 firmware includes several automatic and manual overclocking options in addition to Asus OC Tuner, which is designed to automatically find the company's idea of an optimized overclock based on incremental clock increases and stability tests. We’re a little cautious with core voltage settings, though, and prefer to set this manually.
We didn’t quite reach 4.7 GHz on the P9X79, but small 0.1 MHz BCLK increments allowed us to set 4672 MHz using the same 47x CPU multiplier.
The P9X79 plays on our love of simplified menus by placing key voltage controls on the main Ai Tweaker menu. Per-channel DRAM reference voltage levels might be perceived as over-the-top, however, since only the most persistent tweakers use these.
Choosing “Ultra High” CPU Load-line Calibration from the DIGI+ Power Control submenu allows us to retain a CPU core voltage very close to our targeted 1.35 V under heavy processor loads.
Disabling EIST within the CPU Performance Settings submenu let us lock in a constant 47x CPU multiplier, exceeding non-Turbo Boost ratios even though the menu shows Turbo Mode disabled.
The P9X79’s DRAM Timing Control submenu adds slew rate to the familiar primary, secondary, and tertiary timings.