Some results (ver 10.3 vs 10.5):
Radeon Vega 56: 0.7 CPD -> close to 0.8 CPD
Radeon Nano: 0.5 CPD -> close to 0.6 CPD
Radeon Rx 480: 0.4-0.42 CPD -> 0.43 CPD
Rx 480 doesn't give me 0.5 CPD, what sieve size and similar settings should I try to get there?
Nano and Fury(X) also can get +20% performance, good...
For RX480 - not need any changes in config.txt except kernelType="asm", but possible need install more new drivers and remove all *.bin files after. Asm kernel don't like too old (2016 year) Crimson and amdgpu-pro drivers.