What was the first chess engine that could beat the world champion on a standard desktop? What was the first chess engine that could beat the world chess champion when running on a standard desktop playing at standard speeds (i.e. not blitz chess)? For concreteness, say a $1000 PC.
Deep Blue was a super computer. In the 2006 match, Kramnik was defeated by Deep Fritz that everybody could buy.


  In a November 2006 match between Deep Fritz and world chess champion
  Vladimir Kramnik, the program ran on a computer system containing a
  dual-core Intel Xeon 5160 CPU, capable of evaluating only 8 million
  positions per second, but searching to an average depth of 17 to 18
  plies in the middlegame thanks to heuristics; it won 4–2.[31][32]  


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