Guy, am I missing some settings, or in general RX4XX is slower than RX5XX?
the main differences are 8 gb or 4 gb, then your memory straps, then core / mem speed and the intensity settings...
(my rx480 gives 740 h/s on heavy, but it is a 4 gb elpida, my rx580 1110 h/s but 8 gb hynix)