The Tv and GF card issue
This sounds to me like XF86Config-4 does not have an entry for
your tv settings. This is why it is complaining about there being
nothing defined about it.
If you go through the configuration file you will find that there are
definitions for the display on your system.. effectively what you
need to do is to create a seperate definition for the display type
that you have ( the tv ) with all of the same fields as the normal
monitor definitions, but chnaged to reflect the abilities of your TV.
Once that is done you should be able to make the alterations in
the configuration that refer to that definition you have provided.
I'm afraid that I cannot give you more information than that, but
I am sure that someone has actually done this themselves and
can give a step by step guide.