this is my first post in this forum.. I am new to Linux, just installed Ubuntu 11.10 on my Sony Vaio VGN-Z12 with two graphic cards Intel and NVidia Geforce 9300 GS. after the installation the lightdm works on Intel card but with very law display quality. I installed Nvidia driver from the official website as well as this PPA.
sudo apt-add-repository ppa:ubuntu-x-swat/x-updates
sudo apt-get update
sudo apt-get install nvidia-current
once I install the driver and run nvidia-xconfig which creates xorg.conf file the xserver will not start with error "no screen" if I delete the xorg.conf file then I am able to start the xserver normally but with intel display (bad quality)