I use a Samsung U28D590D via Displayport 1.2 powered with an R9 R290. Running on Win 8.1 and at 60Hz.

Looks great, can play games at full res and most programs suit the dpi. No major problems.

However,

Linux is a completely different story. I had a hell of a time getting the drivers to work and after about a week of crashes, reinstalling and trying to tweak the size of things so they were visible I gave up and went back to M$.

So if you can bear Win 8.1 and have a powerful gpu, the reasonably priced Samsung is a good bet.