The S-video cable will carry video only. In order to send sound, you'll need to run a stereo cable from your sound card to the TV. That will probably require a stereo miniplug to RCA cable, such as this:
http://www.flatheadenterprises.com/wp-content/uploads/rca_to_mini.jpg
Hope that helps.
I have a Dell 8300 desktop in my office and I want to hook up the computer to the tv in my bedroom to watch netflix instant play movies.
I hooked up an s-video cable and have the picture but I'm having trouble figuring out how to get the audio to work. I'm not a real savy computer guy so be patient

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