My first post here, as I normally find solutions by searching already answered posts.
I have a dell latitude E6420 and it comes with an Intel gpu connected to the LCD and an Nvidia quadro connected to the Hdmi port.
When I boot Ubuntu 12.04 with no Xorg.conf file, X detects the intel one and the LCD works properly - but the Nvidia board is not detected and don’t even listed on XrandR.
The distro drivers are installed properly (they seem to be, at least), but running ‘nvidia-xconfig’ creates a buggy xorg.conf that makes both gpu’s unusable.
After making many experiments I came with a xorg.conf that allows the intel+LCD work while apparently loading the GFX from nvidia.
But the quadro gpu is still not working.
Well, you can see in the https://docs.google.com/file/d/0BxF1aA08GvRxQlV0M0NnSW9BV00/edit nvidia-bug-report.log.gz the X log and the conf file created.
Also, opengl is not working on the intel gpu with the nvidia drivers installed.