If running ppa-purge xorg-edgers doesn't work, try the following:
sudo apt-get remove xserver-xorg-video-all
This will then allow you to upgrade from Ubuntu 13.10 to 14.04.
If running ppa-purge xorg-edgers doesn't work, try the following:
sudo apt-get remove xserver- xorg-video- all
This will then allow you to upgrade from Ubuntu 13.10 to 14.04.