Oh, the GeForce 4 MX series are actually GeForce 2 cards. I would look at the card if I were you to see what kind of TV decoder is on it, because it's probably not built in.
Never mind, your persistance paid off, I actually looked up an article on it:
"But as you can see, there is no TV-Out encoder chip on the card. That’s because the NV17 (GeForce4 MX) has integrated VPE on chip that allows for TV-Out up to 1024x768" Read the entire article at <A HREF="http://www.mikhailtech.com/articles/video/gainwardmx440/" target="_new">http://www.mikhailtech.com/articles/video/gainwardmx440/</A>. That should solve your problem.
<font color=blue>At least half of all problems are caused by an insufficient power supply!</font color=blue>