S-video connection Dell Inspiron 6000 to TV

Hello,
I have a dell inspiron 6000. I have an s-video cable that connects from the back of the computer to my mitsubishi TV. How do I get the picture on my computer to display on my TV? I have the s-video cable connected, but obviously I need to do something else as nothing displaying on the TV. On the TV it does come up input 3 s-video, but nothing else. Please help me figure it out. Must be somthing with the settings. Thanks a bunch.......Jeff