Why would it come with one of those? By searching on the site that image was on, the card you own is a XFX GeForce 7900 GT 256MB PCI-E XXX Edition? Or something made by GeForce, obviously.
We get this image after a
quick search on Newegg:
That's a custom Output->HDTV cable. Not an S-Video->HDTV cable.
In any case, I'll do a bit of research on RGB->Luma/Chroma and get back to you.
-Skyler
EDIT: Brain fart, I actually put together an RGB encoder for a fellow Benheck member. The kit was from Neo-Bitz, and you simply soldered some things up, and it takes in RGB signal, and outputs Composite and S-Video. Although originally designed for the Neo-Geo AES, it should work as a general solution. The site is at
http://neobitz.com/ , and the DIY Encoder goes for pretty cheap at ~$30 USD. There are more expensive alternatives such as
THIS, but I don't recommend it (very expensive...)
If I find more, I'll let you know.