Crowning a rookie chess champion.

The heavy burden of high expectations lay over the rookie Hitech when it made its first move last week at the North American computer chess championship. Three days and four matches later, Hitech was the undisputed title holder. Left far behind was the reigning world champion CRAY BLITZ (SN: 10/29/83, p. 276)). Raw speed was no longer enough.

Newcomer Hitech was created by Hans Berliner, a former world chess-by-mail champion, and a crew of assorted experts at Carnegie-Mellon University in Pittsburgh. In this custom-built chess machine, an "oracle," running on a Sun minicomputer, encodes chess knowledge while a specially designed "searcher" does the work.

Before the start of a search for the best move, the oracle analyzes a chess position and decides what information the search must uncover. Then each one of the searcher's 64 integrated-circuit chips is loaded with its assignment. Each chip, working in parallel, comes up with its own idea for the best move and passes a numeric score back to the oracle, which acts as an arbitrator.

"We have a faster move generator than anybody has ever had," says Berliner. "But we also have some idea of the 'goodness' of the moves as they come off the production line." The system is organized so that increasing the computer's chess knowledge doesn't lengthen search times. Hitech's knowledge base can be expanded indefinitely.

This design overcomes a major constraint often faced by programs like CRAY BLITZ, which run on supercomputers. A computer without Hitech's special architecture has to choose between taking a cursory look at millions of positions or a more careful, informed look at fewer positions.

The same feature may also have practical value. Berliner is exploring the possibility of using a similar architecture for determining molecular structures. Given a substance's chemical properties and the number of atoms of each type present, the computer would try various combinations and score them, says Berliner, "just like you score chess positions."

Hitech played its first game last May. Since then, it has progressed rapidly. In a tune-up tournament a week before the championship, Hitech played three human chess masters, winning two games and drawing one. It won the tournament and achieved a performance rating of 2530. This puts Hitech within striking distance of a grandmaster rating. World champion Anatoly Karpov is rated at 2705.

Ten chess machines and computer programs vied for the title at last week's championship in Denver. Although some longtime competitors and former champions like Belle and NUCHESS were missing, others saw this tournament as an important warm-up for the world championship next June in Cologne, West Germany.

The results were encouraging for custom-built chess machines. Another such machine, BEBE(SN:11/5/83, p.303), placed second, while CRAY BLITZ won only two of four games to end up tied for fourth place. One surprise was Intelligent Software, a program running on an Apple computer, which placed third.

"Bacically, it's a tough league," says tournament organizer Monroe Newborn of McGill University in Montreal. "The competition is fierce. People are working very hard. The work is paying off."