black side bars 16:9 content

Hi,

I have connected a LG55C7V to my HTPC running Kodi 17.1
I am seeing black bars on the side when playing 16:9 content, and I’m not sure exactly what part of my configuration I can improve…

I am running Windows 10 (creators update). I have set the resolution to 4096×2160, which is the maximum reported resolution. I was a bit surprised that I could choose this resolution, since the resolution in the TV specifications is 3840×2160. Windows 10 actually shows 3840×2160 as the recommended resolution. However if I choose 3840×2160, then I am seeing small black bars on the left and right side of the Windows UI. The vertical area is completely filled.
Choosing the 4096×2160 resolution let the Windows UI fills my entire screen in both horizontal and vertical directions. The Kodi UI also takes op the entire scree.

When I play content in 16:9 aspect ratio I will see small black side bars on the left and right. I can understand why, since 3840×2160 is 16:9. So it does not fill the remaining pixels. But then how should I configure it?
Should I actually set windows to 3840×2160? But then how do I let it fill my entire TV screen?
I’m a bit confused Smile