“Resolution alone does not guarantee a better image; refresh rate is important too, which for 4K is mainly limited by the bandwidth of the video interface. Over HDMI 2.0 and DisplayPort 1.2 the maximum refresh rate is limited to 60Hz, which is better than the 30Hz of HDMI 1.4 but arguably still slow enough that image quality -- particularly on moving images -- is affected. The most recent standard, DisplayPort 1.3, supports 4K at up to 120Hz refresh and may appear in products in 2016.”