Screen size above 1

I have some tall trees around 10k vertex. I was planning to show the LOD0 only if the player is really close to them. So I tried to set the screen size to 1.5 in the LOD settings, but the value is always resets to 1. I have tried to use platfrom specific override too, but it seems it seems it doesnt have any effect. How can I increase the screen size above one?

289059-screensize.png

Change the resolution on Desktop as similar to previous versions of Windows. Right-click anywhere on the desktop and select “Screen resolution”.
Click the Resolution drop-down menu. If there are multiple types of display resolution, select the type you want to adjust from the Display menu

I’m afraid you seriously misunderstood my question. I added an extra image attachment to my question. I hope now my question is much more clear.

Oh sorry, my bad