Deep Blue vs Kasparov

The matches that changed chess forever. In 1996 and 1997, IBM's Deep Blue challenged World Champion Garry Kasparov in the most significant human-computer chess matches ever played.

1996
Kasparov wins 4-2
1997
Deep Blue wins 3.5-2.5
200M
Positions/second evaluated

What Was Deep Blue?

Deep Blue was a specialized chess computer built by IBM, developed by Feng-hsiung Hsu, Murray Campbell, and Joe Hoane. The 1997 version ran on an IBM RS/6000 SP supercomputer with 480 specialized chess chips. It could evaluate 200 million positions per second and look ahead 12-14 moves in complex positions.

Hardware
IBM RS/6000 SP
Chess Chips
480 custom ASICs
Speed
200M pos/sec
Depth
12-14 ply

1996 Match: Philadelphia

Kasparov won 4-2. The World Champion proved too strong, but Deep Blue won Game 1, sending shockwaves through the chess world.

G1
Deep Blue vs Garry Kasparov0-1

Kasparov played the Sicilian and after a complex middlegame, Deep Blue could not withstand the World Champion's pressure.

G2
Garry Kasparov vs Deep Blue1-0

Kasparov won with White in a positional game, outmaneuvering the computer.

G3
Deep Blue vs Garry Kasparov1/2-1/2

A hard-fought draw. Kasparov could not break through.

G4
Garry Kasparov vs Deep Blue1-0

Kasparov outplayed the computer positionally.

G5
Deep Blue vs Garry Kasparov1/2-1/2

Another draw. Kasparov could not win with Black.

G6
Garry Kasparov vs Deep Blue1-0

Kasparov won the final game comfortably.

1997 Match: New York

Deep Blue won 3.5-2.5. The most controversial match in chess history. Kasparov accused IBM of human intervention.

G1
Deep Blue vs Garry Kasparov1-0

A shock. Deep Blue won a complex game, playing moves that seemed almost human. Kasparov appeared shaken.

Key: Deep Blue showed a dramatically higher level than 1996. The computer played with surprising subtlety.
G2
Garry Kasparov vs Deep Blue0-1

The pivotal game. Kasparov adopted an unusual opening but Deep Blue defended accurately. In a complex position, Kasparov suddenly resigned, believing his position was lost. Analysts later found he could have drawn. The most controversial game of the match.

Key: Kasparov's resignation in a drawable position suggested psychological collapse. He accused IBM of cheating, claiming moves seemed 'too human.'
G3
Deep Blue vs Garry Kasparov1/2-1/2

Kasparov played creatively for a win but could not break through.

Key: Kasparov fought hard but Deep Blue was relentless.
G4
Garry Kasparov vs Deep Blue1/2-1/2

Another draw. Kasparov was visibly frustrated.

Key: The match was slipping away from Kasparov.
G5
Deep Blue vs Garry Kasparov1/2-1/2

A fighting draw. Kasparov needed to win Game 6 to tie the match.

Key: Everything came down to the final game.
G6
Garry Kasparov vs Deep Blue0-1

Disaster. Kasparov played a terrible opening (the Caro-Kann, which he rarely played), was outprepared, and resigned after just 19 moves. The shortest game of the match. Deep Blue won the match 3.5-2.5.

Key: The moment a computer beat the World Chess Champion in a match. Kasparov's 19-move capitulation was shocking. IBM's stock rose 15% that day.

The Controversy

After the 1997 match, Kasparov demanded a rematch. IBM refused, dismantled Deep Blue, and the computer was never seen again. Kasparov accused IBM of cheating, claiming that moves in Game 2 appeared to show human intervention, not pure machine calculation.

Specifically, Kasparov pointed to Game 2, where Deep Blue made a subtle positional move (36.axb5) instead of a more natural material-winning move. Kasparov believed this showed human guidance. IBM denied any human intervention during games.

IBM's refusal to grant a rematch and their dismantling of Deep Blue fueled conspiracy theories. The controversy has never been fully resolved. Many in the chess community believe that while Deep Blue legitimately won, IBM's handling of the aftermath was deeply unfair to Kasparov.

The broader significance is clear: regardless of the controversy, 1997 marked the beginning of the end for human supremacy in chess. Within a decade, no human could compete with the top computers.