sudo apt-get install --reinstall xorg xserver-xorg xserver-xorg-core xserver-xorg-video-intel libegl1-mesa mesa-utils mesa-utils-extra libegl1-mesa-drivers mesa libgl1-mesa-dev libgl1-mesa-dri libgl1-mesa-glx xserver-xorg-video-all xserver-xorg-video-nvidia xserver-common
sudo dpkg -l|grep nvidia|cut -d" " -f3 |tr "\n" " ">/tmp/t
sudo apt-get remove --purge cat /tmp/t
sudo nvidia-uninstall
sudo apt-get remove --purge bumblebee
sudo apt-get purge xserver-xorg-video-nvidia
sudo apt-get install --reinstall xorg xserver-xorg xserver-xorg-core xserver-xorg-video-intel libegl1-mesa mesa-utils mesa-utils-extra libegl1-mesa-drivers mesa libgl1-mesa-dev libgl1-mesa-dri libgl1-mesa-glx xserver-xorg-video-all xserver-xorg-video-nvidia xserver-common