R9 in general are very hot running cards. They also are not very efficient as the 900 line atm. They 390 is a slightly rebadged 290 series card but they have binned there parts so that they are the ones AMD finds can withstand the higher clocks that the 390 ships with, you can flash a 290's bios to reflect its 390 equivalent brother and it will work but not as efficiently as the parts will be struggle or soon fails since they were never binned for that stress. I would recommend a 970 myself for what games you want to play and since you can only be single card anyways (SLI has issues too). Also a 290x will be cheaper now with pretty much same performance at 1080p if that is what your running I run 1440p and don't even fill my 6GB of vram.