Dim monitor although dim option is missing

Hello everybody.
It is my first post in this community, so I do apologize in case this is not the right place to post.

I am using Gnome 43.2 (wayland session) on Arch linux with a Ryzen 5900HX.
Under Gnome-settings->power there is no dim-screen option (I guess because my computer is not a laptop).

Because I am connected to a smart TV through HDMI, I was wondering if one of the possible things is possible to do when the computer is idle:

    1. Turn off the TV without but keeping the HDMI audio
    • I have read that this was possible with x-org sessions disabling DPMS
    1. (if 1) is not possible) Dim the screen at very low brightness (the audio would keep working)

Sorry in case my explanation is not very clear.

Thanks a lot in advance