My Vega 64 gained 12H/s vs 1.6.9 on v8. Stable at 2134H/s, power consumption remained the same.
Nice hash rate, whats your miner settings? Did you modify your mem clocks?
1488/1149@863mV, "intensity" : 123, "worksize" : 16, "threads" : 2, "fragments" : 16