That AOC is a 1080P panel (1920x1080 resolution) the Monoprice 27" is 2560x1440 so it’s substantially more pixels and much higher DPI. Just think of it as the difference between the Pre-retina and post retina iPhone.
Technically the Monoprice is also a 10 bit (Vs 8 bit) panel for the AOC, (it has a higher ability to reproduce color) but it can’t really be taken advantage of.