You are looking at more than a cable. Computer graphics and normal broadcast television are incompatible with each other. You will need some form of convertor which is normally built into graphics cards with TV out. Your card has no TV out facility and the DIN socket is only to do with enhanced stereo effects on graphics.
You will need some form of hardware covertor but I cannot help asto where you can get it.
I am sure other members will be interested if you get a solution