Ubuntu 18.04 on Asus X550V
Getting Ubuntu 18.04 to work on an Asus laptop with Nvidia graphics using a few grub boot flags.

Intro

Ubuntu does not play nice with hardware. Especially Nvidia graphics. The X550V Asus laptop comes with a Nvidia GeForce GTX 950M card. In addition, something about PCIE seems to mess things up during the install. I found this bug, but that only solved my graphics problem. I still had locked CPUs, screens upon screens of PCIE errors, and frozen screens after log in. All it took were a few grub flags and it worked just fine.

Install Ubuntu

For the installation, make sure to edit the boot flags. Replace quiet splash with nomodeset acpi=force intel_idle.max_cstate=1 pci=nomsi pcie_aspm=off. Then run your installation as normal and reboot. This time add nouveau.modeset=0 acpi=force intel_idle.max_cstate=1 pci=nomsi pcie_aspm=off the end of the line that starts with linux. Your laptop should boot without issue. Once logged in modify the file /etc/default/grub so it reads:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi=force intel_idle.max_cstate=1 pci=nomsi pcie_aspm=off"

Then update grub sudo update-grub. Go to the “additional drivers” tab of Software and Updates and select the appropriate Nvidia driver for your card. As of this writing, it is nvidia-driver-390. Save the changes and reboot. There you have it. You should have a fully functioning system now with the latest Nvidia driver. Note: I have no idea why those grub flags work or even what they do. This worked for me, and that’s the only guarantee I make.

Other Flags

I tried quite a few flags and combinations during my attempted install of Qubes:

video=vesa:off
inst.text
nouveau.modeset=0
rhgb
rd.driver.blacklist=noveau
nouveau.noaccel=1