If you don't want to overclock the card, get the rx 480. I think that in two years time the gap in DX 11 games will be very small and enough DX12 games and patches will be released so that RX 480 will overtake the GTX 980 overall. In that case you will get better performance and more money when you sell the card to buy a new one.
I remember when R9 290 came out that GTX 780 was on par with it, but today it is a whole different story.
I was astonished by the perf/watt ratio of the cards, wonderful work by NVIDIA. But now it seems to me that they were pure gaming cards, while AMD'S GCN was very underutilized delivering similar performance and therefore consuming much more. Now newer APIs provide opportunity to squeeze more performance from that cards.
