One of the other issues that you run into with 4K gaming and G-SYNC is that you will frequently drop below 40 FPS in demanding games. At that point, the on-screen pixels begin to decay and you can see a noticeable flicker. That's one more reason to stick with a lower resolution, as staying above 40 FPS isn’t as difficult, but there are other potential benefits. With a 144Hz maximum refresh rate, rather than only drawing a frame twice when the refresh rate drops below 30Hz, it’s possible for G-SYNC to draw frames twice at anything below 72FPS, at which point flicker shouldn’t be an issue. It’s not clear whether or not ASUS (or NVIDIA G-SYNC) do this right now, and the response when I asked was a cryptic “we are not releasing any implementation details on G-SYNC right now”, which means it may be a future feature (and there’s likely a bit of overhead with drawing a frame twice). It would be smart to at least draw twice at frame rates below 45 FPS, though, as that’s when flicker starts to become a problem and there’s no reason a 144Hz display couldn’t refresh twice (effectively 90Hz).