@gamingonlinux The worst I ever ran into was a system that, after updating, blinked between a getty login prompt (no gdm) and a black screen. And when the screen was black, it didn't respond to keyboard input.

My best guess is that it had fallen back to framebuffer mode, but for some reason the kernel was taking an extremely long time to render anything, which hard locked the kernel until it was done drawing the screen.

Reinstalling the latest version of my OS fixed this.