Asus’ UEFI includes a custom-configurable start page with XMP and fan settings, called Easy Mode. But if you really want to make changes easily, you'll instead set the boot options to kick you into the “Advanced Mode”.
Enabling XMP in Advanced mode means choosing XMP as an overclocking baseline, and making additional adjustments from there. The Ai Tweaker menu starts off with that setting, strap ratios for BCLK overclocking, and eventually BCLK frequency.
Further down the Ai Tweaker menu are CPU multiplier, DRAM frequency, and DRAM timing controls.
We’re three pages down the list before we reach CPU voltage controls, but are instantly made happy by one of our findings. While most enthusiast-class motherboards purposely add somewhere around 10% to both set and reported voltage, the Z87-WS gives us 1.25 V at its 1.25-volt setting.
DIMM voltage, on the other hand, turns up the same old tricks we've been observing for a while now from many board vendors. In order to achieve the best memory stability, Asus' Z87-WS adds around 30 to 35 millivolts to our chosen setting. Test consistency and accuracy demands that we choose 1.62 V to achieve the proper 1.65 volts.
Three pages of DRAM settings cover the expected range of primary, secondary, and tertiary options, along with a few additional wave form controls.
Default settings for the Digi+ Power menu provided our hardware with excellent voltage stability.