I've did
sudo apt-get purge nvidia* sudo apt-get install --reinstall xserver-xorg-video-intel libgl1-mesa-glx libgl1-mesa-dri xserver-xorg-core sudo dpkg-reconfigure xserver-xorg sudo update-alternatives --remove gl_conf /usr/lib/nvidia-current/ld.so.conf I've also blacklisted nouveau driver
/etc/modprobe.d/blacklist-nvidia-nouveau.conf blacklist nouveau options nouveau modeset=0 But when i try to run glxgears it renders nothing(black screen).
$ vblank_mode=0 glxgears ATTENTION: default value of option vblank_mode overridden by environment. Errors in xorg log:
grep "EE" /var/log/Xorg.0.log (WW) warning, (EE) error, (NI) not implemented, (??) unknown. [ 274.620] (II) Initializing extension MIT-SCREEN-SAVER [ 274.623] (EE) AIGLX error: dlopen of /usr/lib/x86_64-linux-gnu/dri/i965_dri.so failed (/usr/lib/x86_64-linux-gnu/dri/i965_dri.so: cannot open shared object file: No such file or directory) [ 274.623] (EE) AIGLX error: unable to load driver i965 1 Answer
sudo prime-select intel This util is present in ubuntu fresh install.
Next package must be installed.
i A libgl1-mesa-dri - free implementation of the OpenGL API -- DRI modules 
