The problem is amd driver, you can mine a 30mhs in linux with claymore 14.7 and hive os
give us a screenshot for r9 390 in ETC/ETH with 30M/h
http://prntscr.com/orllypWhat clocks and voltages? 113W - It's unbelievable...
Keep in mind you have to add 30-50W for the fan's.
Are you kidding? 30-50W for fans? It must be real BIG fans...
Fans on videocards, even if card have 3 of them, use only several watts of power.