This is a very weird problem I had when I was doing a fresh install on my pc.
16GB DDR4 2400mhz ram
I went through the installation process perfectly fine and after it finished the system rebooted and it failed to boot. Right after it initialized the kernel theere were some weird green artifacts on screen + a high brightness green flash on second montior and the image sort of froze up. I decided to reboot numerous times and the problem remained. I had to spam ctrl+alt+f1 to get to a command line where I installed the latest Nvidia driver. After that all was well but I noticed image retention on my main monitor (Acer Predator 1440p 144hz). I don’t know how to explain it but it had noticeable black lines in the left and right edge of the screen. Thankfully it’s an LCD monitor so after a few hours it turned back to normal but it was a very very strange issue. Anyway had to install another OS for a few days to do some testing but now I’m gonna try installing Endeavour fresh again and will make a video showing the problem if it appears again.
edit: This time it did it only the first time and it fixed itself after a reboot. Here’s a video : https://youtu.be/O5X0rOumzlU