Hi everyone,
In the past I was using my machine with Ubutnu 20.04.4 LTS and a Quadro K420 GPU, with two monitors connected to its two ports. Later, I installed an extra GeForce GT730 as a basic display adapter, to get extra HDMI slots, which I used to connect two extra HDMI fake display dongles.
This was done to be able to save up energy and have a little bit more privacy when connecting to my computer remotely.
Back then, doing this was plug-and-play. Everything worked like a charm, the Quadro K420 remained as the main GPU and I used xrandr to swap between the pairs of screens:
# To use the phsyical monitors
xrandr --output HDMI-1-0 --off --output HDMI-1-3 --off --output DP-1 --mode 1920x1080 --output DVI-I-1 --mode 1920x1080 --right of DP-1
# To use the fake displays
xrandr --otuput HDMI-1-0 --auto --output HDMI-1-3 --auto --right-of HDMI-1-0 --output DP-1 --off --output DVI-I-1 --off
Some months ago, I decided to upgrade my OS to Ubuntu 24.04.4 LTS. Then the nightmare started. I am very far from an experienced linux user so I had to fight a lot with my system to get the drivers, version 470.256.02.
To acomplish it, I followed an amazing guide that is present in this forum (I wasn’t able to find it again), that meant downgreading to kernel version 6.8 to be able to succesfully install that driver. I did that, while latter setting up this 6.8 kernel as the default.
However, that was not the end of my issues, when all 4 displays were connected (two connected to GPU-0: Quadro K420 and two connected to GPU-1: GT730) I was getting a weird padding between my phsyical monitor 1 (GPU-0:DVI-I-1) and my physical monitor 2 (GPU-0:DP-1), making them become a deformed widscreen (I didn’t manage to save any screenshots). Additionally I could only manage them using nvidia-settings and xrandr was giving me problems.
I tried everything, but I ran out of ideas, any help would really be appreciated.
Eventually, as quick fix (just because I needed to use the computer and could’nt spend more time on this) I managed to set the HDMI fake dongles (GPU-1:HDMI-1 and GPU-1:HDMI-2) to a separete X session (X session 1), using only my physical monitors, both set up in X session 0, being able to manage them using xrandr. However, now I am unable to access to this X session 1 nor to return these HDMI screens to X session 0 (using nvidia-settings).
I need help, please!
Probably my question is missing log/config files, however I don’t know what will be need it. Just ask and I will provide whant is necessary (if I can).