External GPU (eGPU) + NVIDIA Drivers on Linux: Solving the Display Manager Initialization Problem

External GPU (eGPU) + NVIDIA Drivers on Linux: Solving the Display Manager Initialization Problem TL;DR: If your NVIDIA eGPU works in recovery mode but gives a black screen on normal boot, you're missing one critical Xorg option: AllowExternalGpus . This guide shows how to fix it properly on any X11-based Linux distribution. Introduction Installing NVIDIA drivers on a Linux system with an external GPU (eGPU) connected via Thunderbolt can result in a frustrating black screen instead of your login