It was a bad week for chess champions. As Anatoli Karpov was falling a game behind Gary Kasparov in the world chess championship at Moscow's Tchaikovsky Concert Hall, an upset of a different sort was taking place in Denver's Radisson Hotel. The world's top-ranked chess machine, a $14 million Cray X-MP/ 48 supercomputer running a program called Blitz, was about to lose the North American computer-chess championship to Hitech, a rack of custom-made silicon chips attached to a $20,000 Sun minicomputer.
While Karpov and Kasparov were face to face, the two computers were 750 miles apart--the Cray in Mendota Heights, Minn.,...