Can you use a 4K TV for as a PC Monitor?

Solution
Sure you can. But TV screen got a lot more input lag and running games at 4k resolution will hit your hardware pretty hard. It's the same amount of pixels as FullHD 1080p times 4 so make sure, that your hardware can keep up to the amount of power you're asking from it. :D
Not recommended for stuff like CS:GO, because of the input but anything else than hardcore competitive stuff is totally fine.

migronesien

Honorable
Sure you can. But TV screen got a lot more input lag and running games at 4k resolution will hit your hardware pretty hard. It's the same amount of pixels as FullHD 1080p times 4 so make sure, that your hardware can keep up to the amount of power you're asking from it. :D
Not recommended for stuff like CS:GO, because of the input but anything else than hardcore competitive stuff is totally fine.
 
Solution
Aside from the aforementioned lag, the only other thing to watch out for is that most TVs assume HDMI input is a video source, and will overscan it. You'll have to find a setting on the TV called "1:1" or "PC" or "Direct" or something similar to turn off overscan. Otherwise the computer output will appear blurry.