Puffnstuff :
I tried the rx 580 8gb card this past weekend and at 3440x1440 it couldn't even keep up with my old gtx 780 ti. While playing games it would randomly produce black screens and while playing bf3 it would also flash white screens along with the random black screens. Then the fans were making this horrible buzzing sound so I immediately sent it back to Amazon for a refund.
When the card is defective, there is a facility you can avail called RMA. In a batch of multiple cards, one or two can be defective. That is within acceptable limit for both Nvidia and AMD.
I have myself used the 580 on a 1080p/60hz screen and it is as good as the 1060, if not better.