I also tried Hellaes Guide and got 1800h/s with Vega56 and Stock Bios. PC Idle at 70W and Load 215W so GPU should be arround ~145W.
If I try any of the 3 posted reg files an flashed Vega 64 Bios i get a green Screen at Windows 10 Start and cant get into Windows. Any Ideas why? Voltage to low maybe?