4k problems please help

Right click your desktop and click screen resolution. What does it say?

The website might not account for the possibility of 4k screens. It told me that I'm running an adnormal resolution, even though it is 1080p.

your resolution does not have a common 5:4 (1.25), 4:3 (1.33), or 16:10 (1.6) aspect ratio, which means that images can be distorted. Your aspect ratio is: 1.78.

Clearly this is a very old website that isn't up to the times.
 


It says 4k but my resolution isn't 4k as I've tried it on a different PC and it's much better then this.
 


Which monitor do you have by the way? I don't see anyone mentioning which one it is.