Successful test with 18.8.1 drivers, SRB 1.6.7 and old BinaryKernels from 1.6.7.
V7 speed is excellent...
I have the same speed with bc driver but with less power for 6 GPU RX480: 650w vs 750w))) And of course, with the red warning about not adrenalin drivers)))
I not have the same speed on rx470 (modded bios, driver recomended version 1150 mhz gpu/2225 mem) V7
1.6.6 ~ 905 H/s
1.6.7 ~ 880 H/s
and after the launch of 1.6.7 with a shit speed of 880 it is necessary to full reboot PC so that 1.6.6 starts to recover again >900