ProbeIt
Use a multimeter on the specially designed motherboard points, to accurately monitor the voltages applied to the motherboard and its hardware. This is an advantage for two reasons; firstly it can provide slightly more accurate and a faster response vs software readouts, and secondly an external readout can show the realtime voltage level even while you are gaming or benchmarking.
ProbeIt in the OC Panel

ProbeIt on the GENE and Formula motherboards
Below shows the extended ProbeIt read-out on Extreme motherboards. Above the solder points are yellow clips that enable more advanced multimeters to plug into for long-term monitoring.

ROG ProbeIt on the Extreme motherboards