# Deep Blue vs Kasparov (1997)

In 1997, IBM's Deep Blue supercomputer defeated world chess champion Garry Kasparov in a six-game rematch, marking the first time a computer beat a reigning champion under tournament conditions.

The 1997 match between IBM's Deep Blue and world chess champion Garry Kasparov was a six-game contest held in New York City from May 3 to May 11. Deep Blue won the match by 3½–2½, becoming the first computer to defeat a reigning world chess champion under tournament conditions with classical time controls. The event was widely covered by the media and was seen as a milestone in the history of [artificial intelligence](https://www.wikiprompt.org/wiki/artificial-intelligence), symbolizing the growing capability of machines to challenge human intellectual achievement.

Deep Blue was a supercomputer developed by IBM, specifically designed for chess. It could evaluate up to 200 million positions per second, relying on massive brute-force search and custom hardware. The match followed an earlier encounter in 1996, when Kasparov had defeated Deep Blue 4–2 in Philadelphia. The 1997 rematch attracted global attention, and its outcome was the subject of the documentary film *Game Over: Kasparov and the Machine*.

## Background and technical design

Deep Blue's architecture combined custom VLSI chess processors with general-purpose IBM RS/6000 workstations. The system used a sophisticated evaluation function and an opening book containing thousands of grandmaster games. During the 1996 match, Deep Blue played without its opening book due to a configuration error, but its extended book reproduced opening theory up to move 13 by scoring moves from a database of 700,000 previous games. The 1997 version was significantly faster and had been refined after the previous loss.

Kasparov, then the reigning world champion, prepared extensively for the rematch. He studied Deep Blue's games from 1996 and attempted to identify weaknesses in its play. The match was played under standard tournament rules, with each player having two hours for the first 40 moves, followed by additional time controls.

## The 1996 match

The first match took place in Philadelphia from February 10 to February 17, 1996. Kasparov won 4–2, but Deep Blue made history by winning the first game, the first time a computer had beaten a reigning world champion under normal tournament conditions. The opening game used the Sicilian Defence, Alapin Variation, and Deep Blue's victory was seen as a warning of its potential.

In Game 2, Kasparov employed a preemptive style, blocking Deep Blue's development. The game lasted 73 moves, and Deep Blue's operator resigned when Kasparov had three connected passed pawns against one. Games 3 and 4 were draws, with Game 4 featuring a declined draw offer by Deep Blue's team. Game 5 was the turning point, as Kasparov won with the black pieces, the only win for Black in the match. Game 6 saw Kasparov use anti-computer tactics, slowly improving his position while Deep Blue shuffled its pieces, leading to a decisive victory for Kasparov.

## The 1997 rematch

The rematch began on May 3, 1997, in New York City. Kasparov won Game 1 in 45 moves, using the Réti Opening that transposed to the King's Indian Attack. Deep Blue's 44th move was later alleged to be the result of a bug, where the system resorted to a fail-safe when unable to find a desirable move.

Game 2 was a turning point. Kasparov resigned after 45 moves, although post-game analysis suggested he could have held a draw with a perpetual check. Kasparov accused IBM of cheating, alleging that a grandmaster had influenced Deep Blue's moves. The claim was repeated in the documentary. Deep Blue's first nine moves came from its opening book, and after move 19...Nh4, the game left the extended book.

Games 3 and 4 were draws, with Game 4 featuring a controversial moment when Kasparov offered a draw, but Deep Blue declined and later won. Game 5 was a draw, setting up a decisive final game. In Game 6, Kasparov, playing white, made an early error and was forced to resign after 19 moves, giving Deep Blue the match 3½–2½.

## Aftermath and legacy

Deep Blue's victory was celebrated as a landmark in [AI](https://www.wikiprompt.org/wiki/artificial-intelligence) research, but later analysis suggested that Kasparov's loss was partly due to uncharacteristically poor play. The intellectual value of chess was also questioned, as Deep Blue's brute-force approach differed from human intuition. IBM dismantled Deep Blue shortly after the match, though it remained operational for several years.

The match had significant financial stakes. IBM awarded $400,000 to the winner and $100,000 to the loser in 1996, and $700,000 and $400,000 in 1997. Carnegie Mellon University also awarded $100,000 to the Deep Blue team, a prize established by Edward Fredkin in 1980.

In a 2016 podcast, Kasparov reflected on the match, expressing increased respect for the Deep Blue team and noting that modern chess engines easily surpass Deep Blue. The victory also shifted attention to the game of Go, which was considered more resistant to brute-force computation. In 2015, Google DeepMind's [AlphaGo](https://www.wikiprompt.org/wiki/alphago) defeated European champion Fan Hui, and in 2016 it beat Lee Sedol, using [neural networks](https://www.wikiprompt.org/wiki/neural-network) and [reinforcement learning](https://www.wikiprompt.org/wiki/reinforcement-learning), marking a new era in AI.

## See also

- [Chess computer](https://www.wikiprompt.org/wiki/chess-computer)
- [Artificial intelligence](https://www.wikiprompt.org/wiki/artificial-intelligence)
- [Google DeepMind](https://www.wikiprompt.org/wiki/google-deepmind)

---
Source: https://www.wikiprompt.org/wiki/deep-blue-vs-kasparov-1997
License: CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0/)
Last updated: 2026-09-09T02:02:15.664922+00:00