http://en.wikipedia.org/wiki/Deep_Blue
The system derives its playing strength mainly out of brute force computing power. It is a massively parallel, 30-node, RS/6000, SP-based computer system enhanced with 480 special purpose VLSI chess chips. Its chess playing program is written in C and runs under the AIX operating system. It was capable of evaluating 200,000,000 positions per second, twice as fast as the 1996 version. In June 1997, Deep Blue was the 259th most powerful supercomputer.