If you're also going to use the GPU for gaming, I'd go 390 or Fury Nano. I bought a Fury Nano for mining, and when I'm not playing games, I have it undervolted, consuming less than 110W, and mining at > 20Mh/sec.
The 390 undervolted will consume around 175-185W and give you ~22Mh/sec.
I'm not...