Question how to setup TV with PC to have high res?

When you right click on desktop/display settings, there should be a 1 and 2 (number of monitors) shown. If you don't click to the specific monitor that is capable of the higher resolution you will only see settings for main. Based on what you are saying I am of the impression that your #1 monitor is a 1080p?
 
When you right click on desktop/display settings, there should be a 1 and 2 (number of monitors) shown. If you don't click to the specific monitor that is capable of the higher resolution you will only see settings for main. Based on what you are saying I am of the impression that your #1 monitor is a 1080p?

Yep I know, I do switch to the 2nd monitor before trying to change the resolution
 
As an experiment I've tried to change the cables and connected the HDMI-HDMI and it worked. I had DP to HDMI and unfortunately I have only one HDMI output on my GPU and it taken for my VR set. So I have a question is HDMI splitter may be a solution here, will it pass the UHD signal to both devices VR set and TV?