Nvidia GeForce 930M driver and PCI bus error
I had exactly the same problem on Asus R556U. The problem was solved by booting with pci=nomsi (found the solution on this page)
In order to boot with pci=nomsi:
sudo cp /etc/default/grub /etc/default/grub.bak
sudo -H gedit /etc/default/grub
once the file is opened in gedit replace
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"
with
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash pci=nomsi"
Save and close gedit window. Update grub and restart your system:
sudo update-grub
sudo reboot