How to force 16:9 format?

[fastfed]

Im using a 34" ultrawide and for some reason its stretching it full screen, regardless of my resolution settings in the game.

Im using TMO mod and still forces full stretched screen. I want the 16:9 format with black lines on the sides like I can get with even SH3.

Thanks

[fastfed]

OK well I guess if someone searches I will keep this up because I figured it out.

First you need to set windows display resolution to whatever you want in a 16:9 format, I used 2560x1440. It still didn't work unless I used my native hz of the monitor, so I usually keep these older games to 100fps but it was still stretching it. until I changed it to my native 165fps.

It now works perfect