Linux MX25 LightDM Nvidia Issue - Google Search

To fix LightDM on your cloned MX 25 Linux (Xfce) system, the most common issue is a stale Xorg configuration or a driver mismatch between the original NVIDIA GPU and the new NVIDIA iGPU.

1. Remove Stale Xorg Configuration [1]

Cloning often carries over a /etc/X11/xorg.conf file hardcoded for the old GPU. This is the primary reason for a black screen or LightDM failing to start. [2, 3]

  • At the black screen, press Ctrl + Alt + F1 to enter the TTY console.
  • Log in with your username and password.
  • Rename or delete the old configuration file:
    sudo mv /etc/X11/xorg.conf /etc/X11/xorg.conf.bak
  • Check for any NVIDIA-specific snippets that might interfere:
    sudo rm /etc/X11/xorg.conf.d/20-nvidia.conf (if it exists)
  • Reboot: sudo reboot. [2, 4, 5, 6]

2. Reinstall Drivers for the New Hardware [7]

If removing the config doesn't work, the driver version from the previous system might not be fully compatible with the iGPU.

  • From the TTY (Ctrl + Alt + F1), use MX Linux's dedicated tool to purge the current drivers:
    sudo ddm-mx -p nvidia
  • Reboot your system. It should now boot using the open-source Nouveau driver, allowing you to reach the desktop.
  • Once on the desktop, open the MX Nvidia Driver Installer from the menu to detect and install the correct driver for your current NVIDIA iGPU. [2, 8, 9, 10]

3. Clear Stale User Configurations

Sometimes user-specific display settings from the previous hardware cause Xfce to fail upon login. [11]

  • In the TTY or terminal, run:
    rm ~/.config/xfce4/xfconf/xfce-perchannel-xml/displays.xml
    rm ~/.Xauthority [11]

4. Advanced: Force Early Driver Loading

If you still see a black screen, ensure the kernel loads the NVIDIA modules early enough for LightDM. [12]

  • Create or edit the file: sudo nano /etc/modules-load.d/nvidia-drm.conf.
  • Add this line: nvidia-drm.
  • Save and exit (Ctrl+O, Enter, Ctrl+X) and reboot. [13, 14]

Would you like the specific terminal commands to check your current GPU model and verify which driver is currently active?