LMU Triple Screen rendering on Samsung G9 - 5118x1440

LMU Triple Screen rendering on Samsung G9 - 5118x1440 Custom resolution Wayland

The tutorial works, but in most of my test on simracing this leads to some kind of stutter.
In general its better to use the default resolutions for simracing at least in my monitor.
If your customm resolution is not for simracing then this totally works.

Needed to find current monitor, Install:
edid-decode

Find your monitor, thats annoying, I know mine is this, yours is probably somewhere in this path to:
edid-decode /sys/class/drm/card1-DP-1/edid

When found, save original edid:
cat /sys/class/drm/card1-DP-1/edid > ~/monitor_original_edid.bin

Download CRU:
https://www.monitortests.com/forum/Thread-Custom-Resolution-Utility-CRU

Run CRU with wine, click import and select the edid saved above.
- On Extension blocks double click DisplayID. 
- On the opened window, double click "Detailed Resolutions".
- Now double click the resolution you want to edit, change from 5120 to 5118. That's it.

- Press ok untill you return to the main window that has the import and export, this time click export and name it 
something like monitor_original_edid-5118.bin

Now lets load the changed edid to the monitor, fix path to your monitor:
cat monitor_original_edid-5118.bin > /sys/kernel/debug/dri/1/DP-1/edid_override 
echo 1 >/sys/kernel/debug/dri/1/DP-1/trigger_hotplug

Now you should already have the new resolution available on your desktop.
Set LMU config files, you can even find mine there:
https://community.lemansultimate.com/index.php?threads/triple-screen-rendering-on-ultrawide-samsung-g9.814/page-5

Important fix for LMU stutter, you need to set the perfect resolution on the Settings.JSON, in my case for smooth 120fps:
"Max Framerate": 119.999,

You can get the full refresh rate on CRU where you set the 5118 resolution.

Also, this resolution goes away on reboot I think, use/adapt this guide:
https://gist.github.com/srlemke/6713ef3c507d0d57fcbdf1e62988eb2d
to make it run automatically everytime, works without error for me, its a systemd unit that runs once when system starts.