http://www.linuxquestions.org/questi...d.php?t=533514
Post # 8 of this thread shows my xorg.conf file.
Without knowing which nVidia card or driver you are using, I can't be very specific, but in my case, I have a GeForce4 MX440, which is a 'dual head' card.
I have it set up with this file, which allows me to have the second output of my card connected to a television, so I can watch movies on the TV, while using the computer on my monitor.
It is set up in this file as"Dual Screens using Xinerama", but with very few modifications, you can adjust this file, or at least copy the parts you need, to set up your laptop using the 'Clone' option, which if I am not mistaken, is what you want: you want the same thing on the monitor as is on the projector, correct?
Also, I recommend going to the nVidia website and if you haven't already, download the README file which corresponds to your driver or card, and specifically look into the options "Xinerama", "Twinview" and "Configuring TV-Out".
Hope this points you in the right direction