I have a 6 or 7 year old Dell XPS desktop with a radeon 9800. Today during playing L4d 1 for the first time, it overheated; upon opening the case the whole inch-diameter fan had fallen off, a little plastic piece attaching it to the card had partially melted. I'm typing on the computer now still (with a gigantic fan blowing on the open case) and need to replace the card. My computer was fairly state of the art at the time but now is virtually ancient. What new GFX cards can I get that will work with my old motherboard and powersupply? Do I need to worry about it or can I buy anything. In depth help, please!