Ubuntu won't boot on Asus Zenbook UX431

Asus Zenbook UX431FA i5-8265U CPU, Integrated Intel UHD Graphics 620, Dual boot with windows 10

Ubuntu 18.04 LTS don't boot. I either get stuck on a blank purple screen, or right now, a blank purple screen flashes before going to a blank black screen. I got this laptop in August and still haven't figured out how to fix this. Replacing "quiet splash" with "nomodeset" or booting in recovery mode followed by safe graphics mode does allow it to boot, but then there are issues with display resolution which are bad enough to make certain windows unnavigable.

This problem has been posted and solved elsewhere, however they don't work for me or involve a Nvidia graphics cards which my laptop does not have. I have upgraded BIOS twice and neither time solved the problem. Entering dis_ucode_lds does nothing.

1 Answer

I solved with solution I found in

First boot with nomodeset to get access to system.

As root change working directory to /lib/firmware/edid/

cd /lib/firmware/edid

Download the edid file

wget -c -O ncp.bin

As root modify the kernel boot parameter and update grub menu

nano /etc/default/grub
###
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash drm.edid_firmware=edid/ncp.bin"
###
update-grub2 # for ubuntu

Reboot and the display and brightness control will work