DRM Display to normal Display

[tankhunter8192]

I have used a screen for amazon prime and now it is not showing in OBS, but I would to use the screen as a recording screen for gaming.
How would I convert it to a usable screen?

 

[tankhunter8192]

I found the problem. It was that I had the "Portable Mode" activ and then it just uses one gpu and not all gpus