Failing to create Xorg.conf for Multiple Nvidia GPU Graphics/CUDA configuration

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1

Hello all,

I have been trying on and off for a little over a month to get the correct xorg config for my setup.

I have multiple GPUs: 1x 1080, 3x 3090s.
My current goal is to have my 1080 perform graphical tasks, and the 3090s perform compute tasks, while having each card be able to support overclock settings.

Currently I can run CUDA tasks, but can not overclock my cards or run graphics accelerated programs.

I have the latest ppa drivers installed through MHWD, and the CUDA package installed with pacman.

I think for this to work I need to have my 3090s attached to distinct X screens. I have read several guide that recommend this.
I also think that I need to find a way to disable compute mode on my 1080 on boot, but that could prove difficult. I am willing to pass the 1080 through to a VM with VFIO, and run all of the 3090s headless on the main installation with CUDA, but that would still require me to get the headless X screens working so my overclocks work for the 3090s.

I get an X error whenever I try to boot games. The error text is not in any language I am familiar with, maybe Arabic? Manjaro is configured to use english,
This persists even after disabling compute mode on the 1080. I should note also that the 1080 is the device connected to the monitor.

This is my nvidia.conf:

# nvidia-settings: X configuration file generated by nvidia-settings
# nvidia-settings:  version 470.63.01

Section "ServerLayout"
    Identifier     "Layout0"
    Screen      0  "Screen0" 0 0
    Screen      1  "Screen1" 0 0
    Screen      2  "Screen2" 0 0
    Screen      3  "Screen3" 0 0
    InputDevice    "Keyboard0" "CoreKeyboard"
    InputDevice    "Mouse0" "CorePointer"
    Option         "Xinerama" "0"
EndSection

Section "Files"
EndSection

Section "InputDevice"
    # generated from default
    Identifier     "Mouse0"
    Driver         "mouse"
    Option         "Protocol" "auto"
    Option         "Device" "/dev/psaux"
    Option         "Emulate3Buttons" "no"
    Option         "ZAxisMapping" "4 5"
EndSection

Section "InputDevice"
    # generated from default
    Identifier     "Keyboard0"
    Driver         "kbd"
EndSection

Section "Monitor"
    # HorizSync source: edid, VertRefresh source: edid
    Identifier     "Monitor0"
    VendorName     "Unknown"
    ModelName      "AOC G2770"
    HorizSync       30.0 - 160.0
    VertRefresh     50.0 - 146.0
    Option         "DPMS"
EndSection

Section "Monitor"
    # HorizSync source: edid, VertRefresh source: edid
    Identifier     "FakeMonitor1"
    VendorName     "Unknown"
    ModelName      "AOC G2770"
    HorizSync       30.0 - 160.0
    VertRefresh     50.0 - 146.0
    Option         "DPMS"
EndSection

Section "Monitor"
    # HorizSync source: edid, VertRefresh source: edid
    Identifier     "FakeMonitor2"
    VendorName     "Unknown"
    ModelName      "AOC G2770"
    HorizSync       30.0 - 160.0
    VertRefresh     50.0 - 146.0
    Option         "DPMS"
EndSection

Section "Monitor"
    # HorizSync source: edid, VertRefresh source: edid
    Identifier     "FakeMonitor3"
    VendorName     "Unknown"
    ModelName      "AOC G2770"
    HorizSync       30.0 - 160.0
    VertRefresh     50.0 - 146.0
    Option         "DPMS"
EndSection

Section "Device"
    Identifier     "Device0"
    Driver         "nvidia"
    VendorName     "NVIDIA Corporation"
    BoardName      "NVIDIA GeForce GTX 1080"
    BusID          "PCI:67:0:0"
EndSection

Section "Device"
    Identifier     "Device1"
    Driver         "nvidia"
    VendorName     "NVIDIA Corporation"
    BoardName      "NVIDIA GeForce GTX 3090"
    BusID          "PCI:7:0:0"
EndSection

Section "Device"
    Identifier     "Device2"
    Driver         "nvidia"
    VendorName     "NVIDIA Corporation"
    BoardName      "NVIDIA GeForce GTX 3090"
    BusID          "PCI:8:0:0"
EndSection

Section "Device"
    Identifier     "Device3"
    Driver         "nvidia"
    VendorName     "NVIDIA Corporation"
    BoardName      "NVIDIA GeForce GTX 3090"
    BusID          "PCI:66:0:0"
EndSection

Section "Screen"
    Identifier     "Screen0"
    Device         "Device0"
    Monitor        "Monitor0"
    DefaultDepth    24
    Option         "Stereo" "0"
    Option         "nvidiaXineramaInfoOrder" "DFP-3"
    Option         "metamodes" "1920x1080_144 +0+0"
    Option         "SLI" "Off"
    Option         "MultiGPU" "Off"
    Option         "BaseMosaic" "off"
    SubSection     "Display"
        Depth       24
    EndSubSection
EndSection

Section "Screen"
    Identifier     "Screen1"
    Device         "Device1"
    Monitor        "FakeMonitor1"
    DefaultDepth    24
    Option         "Stereo" "0"
    Option         "nvidiaXineramaInfoOrder" "DFP-3"
    Option         "metamodes" "1920x1080_144 +0+0"
    Option         "SLI" "Off"
    Option         "MultiGPU" "Off"
    Option         "BaseMosaic" "off"
    SubSection     "Display"
        Depth       24
    EndSubSection
EndSection

Section "Screen"
    Identifier     "Screen2"
    Device         "Device2"
    Monitor        "FakeMonitor2"
    DefaultDepth    24
    Option         "Stereo" "0"
    Option         "nvidiaXineramaInfoOrder" "DFP-3"
    Option         "metamodes" "1920x1080_144 +0+0"
    Option         "SLI" "Off"
    Option         "MultiGPU" "Off"
    Option         "BaseMosaic" "off"
    SubSection     "Display"
        Depth       24
    EndSubSection
EndSection

Section "Screen"
    Identifier     "Screen3"
    Device         "Device3"
    Monitor        "FakeMonitor3"
    DefaultDepth    24
    Option         "Stereo" "0"
    Option         "nvidiaXineramaInfoOrder" "DFP-3"
    Option         "metamodes" "1920x1080_144 +0+0"
    Option         "SLI" "Off"
    Option         "MultiGPU" "Off"
    Option         "BaseMosaic" "off"
    SubSection     "Display"
        Depth       24
    EndSubSection
EndSection
2

I know that I have an issue with my xserver screen settings.

I am also wondering if I need nvidia-prime for this setup?

I am expecting there is no need for nvidia-prime as I only intend to render graphics using the primary GPU connected to screen0/ my monitor.