While your system is booting, hold down Shift to get the GRUB menu. This should be done soon after turning your computer on/rebooting.
With Start Ubuntu selected, press E to edit boot parameters. You should see multiple lines of text. Find the following line:
There may or may not be parameters after the equals sign. Typically, they will be "quiet splash", but if they are different, it does not matter. You'll want to add pci=nomsi between the quotes. If there are other parameters in the quotes, add a space after the last parameter. For example:
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash pci=nomsi"
Again, you don't have to have quiet and splash. If it looks different, it is not the cause of your issues anyway.
Once you're finished, press Ctrl + X to boot. Test your system out. If it works, you need to make the change permanent. To do so:
Open /etc/default/grub in terminal with your preferred text editor. Will use nano for these instructions.
sudo nano /etc/default/grub
Now repeat what you did with the boot parameters. Add pci=nomsi to GRUB_CMDLINE_LINUX_DEFAULT= and then save with Ctrl + O and enter. Exit with Ctrl + X. Then run:
The boot parameter will now be used each time you start up.