4k 21-23" low response time monitor?

[KingFaris10]

Hi, I'm looking for a 4K monitor. However, my desk only has space for it to be around 25", as currently I have a 21.5" iMac which has 2.3" air space on the left and 2" on the right too.

I looked on Amazon for a 4K small screen, and I found a Dell one that is 23.8" or something, however it has a response time of 8ms which is too slow for me, as I'll be "gaming".

Any recommendations?

 

[KingFaris10]

Never mind, decided to go for 2k monitors.