The card is GeForce 7300 GT AGP DVI-TV DDR2 512Mb I was told I had to connect it to the power supply and it also has a cable that I have no idea what it is to connect to. It has three receptacles. One for the cable, one for the monitor (the 15 prong one?) and I have no idea what the 24+4 receptacle is for.
Sounds like a DVI adapter. Might be to connect an old-fashioned or cheap analog VGA monitor to the DVI-I port of the card.