For blacklisting an Nvidia GTX1070 gpu on Ubuntu 18.04 with Intel integrated graphics for the host
Blacklist the nvidia driver:
sudo bash -c "echo options nouveau modeset=0 >> /etc/modprobe.d/blacklist-nvidia-nouveau.conf"
sudo bash -c "echo blacklist nouveau > /etc/modprobe.d/blacklist-nvidia-nouveau.conf"
/etc/default/grub: