This caused me some headache last night. I was trying to get the TV-out to work as the main monitor on a Compaq D510 with an MSI nVidia GF4 TI4200-TD. Ubuntu picked the card up OK but I couldn’t get anything on the TV out to work. I spent hours editing xorg.conf with no luck other than buggering up the main monitor settings. I then found a post about removing everything nVidia related and reinstalling, which then allowed nvidia-settings to run (previously this was not found with 7.10 ubuntu so not installed with the default driver).
Then all of a sudden in the nvidia-settings there was an option for enabling tv out – it seems this must set the option on the card, as after a reboot it worked.
Next challenge was to get the TV as the main monitor. It would be setup in classic 2 monitor mode with the main X window on the LCD and the TV as the secondary monitor. I tried every setting of TwinVideo, Dual monitor etc and I could not get it to work. In the end the fix was easy, and found purely by chance – remove the vga connector, then the TV acts as the main monitor. It even posts to the TV as well. Running 1024×768 in SD through S video was a bit hard to read the fonts – increased the size to 14 (or 16, I forget now) but now gives clear readable text, can even use it for browsing!
Next step will be to get a small form factor video card so I can shut the case, then a wireless keyb & mouse. I’ll be setting up MythTV to help make it more girlfriend friendly.