i had the same card.. it runs hot even on 0.8v Core Voltage,

currently running 1110/1950 27.5mh/s on SMos

XFX RS 570 4GB Elpida mem Mem straps 1500 all the way to 2000

on the other hand, Gigabyte was my fav. i can get 29mh/s with 1120 core /2070 mem on 0.8v core voltage for stability. Max 30mh/sec with 1150/2100++ but consume more power.

Sapphire ITX 570 single 6 pin card best i could get 28mh/sec 1090/2050 same 0.8v but the card pulling 84watt on the core.