Screen Uniformity: Luminance
There is no visible light bleed from the XB280HK. Even a 10.12 percent measurement is right on the edge for us; we couldn’t see any problems in normal room light. In total darkness, you can see a slight hotspot at the center of the screen.
Here’s the white field measurement:
The white field result is a little better at 9.07 percent. Regardless of the content you view, this UHD Acer screen delivers a smooth-toned image without any cloudiness or blotching.
Contrast ratio, brightness, chromacity & gamma tracing is where XB280HK looses the ground, but to be fair, most of the gamers won't be noticing much difference at all. But it is kind of disappointing to see Planar do better in these fields than Acer utilizing the same panel. I don't know, maybe the overdrive somehow worsen the results?
But ofcourse, it does well on uniformity and response time. Makes me wonder why XB280HK doesn't have ULMB if it's supposed to be a bundled feature with G-Sync. That should've helped in 60Hz panels more, rather than 144Hz ones.
But anyway, XB280HK looks promising, although I don't think 4K is what I prefer for gaming+life (although I do for gaming only).
It's 1.2a I presume. Since that's what is capable of 4K@60Hz other than HDMI 2.0
People that like to play games also like to play games in ultra HD resolutions.
ULMB uses flickering to lower persistence, which reduces the motion blur. If you've ever used 60hz CRT monitors, you'll know that flickering is painful on the eyes. This is why ULMB mode is not offered on 60hz monitors, and likely won't be offered on anything less than 75-85hz.
Top end GPU's can handle 4K just fine. You just don't play it at max settings. What is better, medium to high settings and 4K, or maxed at 1080p? That is a subjective question, and will vary from person to person.
That said, I prefer higher refresh rates than 60hz, so I'll be going 1440p before 4K.