For run of the mill 1080p 60Hz displays. As to 4K, even a machine of less capability will do the work. Just delays. For full speed UHD play, you are looking at the 1070 GPU and no more than HDMI 2.x connection to a run of the mill UHD 60Hz TV. Gameplay at 4K? Gamers tell me to get to the 1080 GPU.
Please take a look at what I built and let me know if it meets my needs for video editing and gaming:
https://pcpartpicker.com/user/raney24/saved/s7XwVn
Video editing: Nothing too intense, but should be able to handle 4k video and render in decent times. Should also handle most things in After Effects as I make titles and animations.
Gaming: I want to be able to play most games at 60+fps, games like Fortnite and ESO.
Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic