I stopped using power play tables since 18+ drivers. overdriventool is enough to achieve full hashrate at 165W with vega 64 and modified vega 56.
clock: set to 1600, voltage set to 850mV
mem: set to 1100, voltage set to 860mV
real clock is 1400 to 1500 depending of the card ; real voltage: 885 mV; shown in GPUZ.
4 cards rig is at 700W, system uses roughly 35W
Stopped using power play tables?
Do the 18+ drivers allow you to change voltage on lower P states? As far as i know i've been using the power play tables and overdriventool to keep the power consumption down. Not needing the power play tables is new to me.