Im chiming in because im a owner of Samsung UHD 4k Monitor. I run it pretty well now with my Asus Strix 970GTX before I had to play around with optimal settings. On desktop I use 4k resoulution and the monitor is pretty upscaling and clear and crisp. P3D 2.5 I run with 4k but had to put the sliders a notch down and get around 25 fps but smooth and crisp, also with the duke and both pmdgs.
regards
Michael
Driver is performing good, gives a very good AA (SGSS at 2x is end of shimmering in my P3D), little fps gain, but no runwaylights - this is ashowstopper.
regards
Michael