What is the highest video card for windows xp in terms of performance ( price not an issue) available?

Graphic Card companies like ATI or Nividia are always releasing new graphic cards. I would check their websites and look. Don't be suprised to pay $600 for the best.|||go find out|||nvidia 8800 i think ... triple sli capable (3 cards tied together) ... and just one of them performs awesome .... about 800$ i think i saw .. but its probably less than that when it hits the shelves ...