Ok, I recently got a new computer, and I wanted to use the old computer, (my old computer is a 2005 Dell, with Windows XP) in my game room so I could hook it up to the TV in there. So I did some research and I bought a HD 15 to 3 RCA Cable RGB Component Video Cable. I got it today in the mail. So I went up to the game room, hooked it up, and no picture came through. I need help?