did you try to boost your memory speed? I have the MSI RX 480 8GB Armour running at 1290 core 2200 mem. get 30mhz
What strap do you have? I tried 1500, 1625 & 1750 and the core and mem settings are different for each one. I'm currently with 1625 running 1120 core, 2060 mem getting 28.4xx Higher mem and the pc freezes , higher core it restarts