The Japanese government spent $350 million to $400 million to develop the supercomputer over the past five years, Akira Sekino, president and chief executive of HNSX Supercomputers, a unit of NEC Corp. 6701.T of Littleton, Colorado, told the newspaper.

The computer, which is known as the NEC Earth Simulator, was intended to analyze climate changes, including global warming, as well as weather and earthquake patterns, the Times said.

Dongarra said the Earth Simulator had 5,104 processors and could reach a speed of 35,600 gigaflops, or billions of mathematical operations per second.

The old supercomputer speed record, he said, was held by the ASCI White-Pacific computer at the Lawrence Livermore National Laboratory in California. Its 7,424 processors generate a speed of 7,226 gigaflops a second.

The Earth Simulator was formally dedicated in March, and had been installed at the Earth Simulator Research and Development Center in Yokohama, west of Tokyo, the Times said. The Japan Marine Science and Technology Center said on Friday the computer had reached more than 87 percent of its theoretical peak speed, it said.