Vostro 1500 s-video to component not working

I bought a 7 pin s-video to 3 RCA Component cable to hook up my Vostro 1500 to an HDTV. The problem I am running into is that when I have the cable plugged into the laptop and the tv it thinks that it is just a composite cable and does not give me any option to use it as a component cable. Can anyone offer me a suggestion to get this cable to work properly? I've tried using a VGA cable as well but it won't do 720p output from the laptop with it connected. From what I have found on the website people have suggested using the 7 pin s-video cable but nobody seems to have mentioned what to do if it doesn't work as intended.