WE'VE SEEN IT in processors, and it's already happenened in graphics. The rise of the exotics: high-end computer parts that cost hundreds of dollars and promise to take gamers to the extremes of possible performance. These Ferraris made of silicon are growing ever more expensive, and in turn, more exclusive to own. It's a stunning counter-trend in the world of computers, where components consistently drop in price over time as Moore's Law enables wondrous new things. Somehow, these two trends coexist, this creeping exclusivity and the constant march of semiconductor progress. For proof see today's Exhibit A, ATI's brand-new Radeon 9800 XT, a bright red, five-hundred-dollar graphics card with eight pixel pipelines and more bandwidth than a 360 Modena's tachometer. This exotic aims to be the fastest graphics card on the market, and it replaces ATI's similarly pricey Radeon 9800 Pro 256MB, offering even higher performance than its predecessor.