I currently have a 27" Dell that does 1920 x 1200 and a 30" Dell that does 2560 x 1600. My 27" Dell is what I use for gaming since it is 1920 x 1200 but a group of vertical lines appear on the right side when I first power it up. The eventually disappear and are completely gone 30 minutes after the monitor has been powered up. I like the Asus 28" UHD monitor but the Dell would probably also work fine since I don't plan on gaming higher than 1920 x 1080, which would scale perfectly on a 3840 x 2160 display -- much better than the scaling on my 2560 x 1600 Dell. I think ALL of these monitors are TN panels. The 1ns refresh is a dead giveaway. TN might be fine for gaming at 1920 x 1080 and static displays ( desktop/productivity ) at UHD. The "fastest" video cards I have anyway are a GTX 580 in an older s775-based tower and a MSI GTX 760 ITX ( actually faster than a 580, but not by much ) in a water-cooled mini ITX 4770k build based on the Silverstone SG-05 case featuring a Corsair H80i, slim LG BD burner, a pair of WD Black 750GB 2.5" drives, 16 GB Mushkin Redline DDR3-1866 RAM, and Asus ROG Maximus VI with the HD Audio and wireless cards installed. I don't see the point of installing a GTX 780ti in a s775-based quad-core system unless I upgrade that to 4th generation Core i anyway. I'm more into small and quiet these days anyway and hardcore, cutting-edge gaming takes a back seat.
