@CharNoir , try with significant downclock on the memory of the problematic card, or maybe slight downclock, you can check what are the best settings after a while...for exemple, my 7970 is stable on 1300 Mhz (patched bios) , but sometimes i can run for hours with 1315 Mhz....
thanks for replied, my msi r9 390 stock clocks are 1040/1500, how low u think i can downclock it safely? msi afterburner is the tool,right?