[mythtv-users] Nvida card choice for mythtv and gaming

[Stephen Worthington]

On Mon, 11 May 2020 07:00:40 -0400, you wrote:

>Now that I have the GT 1030 working in Xubuntu 20.04 with the Nvidia-440 
>driver, most things like Mythtv are working great.
>
>However, I can't seem to keep the display at 1920x1080 at 60hz. It wants to 
>switch back to 4K which is the EDID or automatic choice by default.
>
>So on boot it uses the /etc/X11/xorg.conf file that the Nvidia X server 
>setting program created to force it to 1080p. But if I switch the AV 
>Receiver away for some period of time from the computer port to DVD 
>player or anything else and then switch back to the computer it comes 
>back as 4K like it forgot how it booted. If I switch away for a short 
>time like 3-5 minutes it comes back in 1080p as I want.
>
>I'm thinking Ubuntu is getting an event triggered by the switching back 
>to computer port of the AVR and using auto settings for the display. If 
>I run Nvidia X server app at this point the configuration settings are 
>in auto instead of 1920x1080 at 60. I can either change it again or reboot.
>
>Or, the display power management mode is getting in the way.  I had it 
>in Presentation mode and Display power management off.  I'm running a 
>test now where Presentation mode is off, but I turned on the Display 
>power management but set the timer settings to 'never'. I see if that works?
>
>Anyone know what's happening?
>
>Jim A

I do not get problems like that since my TV is only 1080p.  When I
play a 4k file, the GPU scales it down to 1080p nicely.

As a workaround, you can use xrandr from a command prompt to switch
the mode manually back to the one you want, maybe something like
"xrandr 60" which would work on my system to put it into 1080p at 60Hz.

I think that if you want it to never go to 4k you will need to do some
more xorg.conf setup to specify the allowed modes, rather than just
the mode at startup.  But if you prevent it from going to 4k modes,
then if you want to play a 4k video file, it will scale it down to
1080p which is a complete waste of your 4k TV.

So maybe you should be considering actually getting it to use 4k mode,
but changing the DPI settings so that text is readable.  I had to do
that for my TV:

Section "Device"
        Identifier "Nvidia GT1030"
        Driver "nvidia"
        Option "DPI"    "100x100"
        Option "NoLogo" "1"
EndSection