Here the best results are at 60 intensity and just one thread. At 1230/2020 I can reach 775~785H/s in my RX570 4GB 4GB Elpida.
How are you able to run 60 intensity, 8 worksize on a 4GB card?
I am only able to run at 51 intensity with 8 worksize. At 52 I get a scratch pad size error, meaning not enough physical mem on the card.
I'm getting around 700H/s for two Hynix cards at 1350/2000.