Apple Monday took a step forward and a step backward in its quest to prove itself a viable player in the world of high performance computing (HPC).

The Cupertino, Calif., computer vendor announced a deal with U.S. Army contractor Colsa to build a 1,566-node supercomputer that is expected to be capable of as many as 25 trillion mathematical operations per second, according to Colsa.

Called MACH 5 (Multiple Advanced Computers for Hypersonic research), the $5.8 million system is designed to do aero-thermodynamic modeling for the Army's Missile Research, Development and Engineering Center. It is expected to be operational by November and, if it were benchmarked today, would rank just behind the Japan Marine Science and Technology Center's $350 million Earth Simulator, Colsa said.

At the same time, an Apple-based supercomputer at the Virginia Polytechnic Institute and State University, which has 1,100 nodes and rocketed to third place last November in the semi-annual Top500 list of the world's fastest supercomputers, failed to appear on a revised version of the list that was published Monday, leaving Apple unrepresented on the Top500.

Virginia Tech, which was Apple's first entry into the top echelons of the world's supercomputers, was unable to submit a benchmark because it is in the process of building a new supercomputer, based on Apple's latest rack-mounted server, the Xserve G5, according to Alex Grossman, director of server and storage hardware at Apple.

Virginia Tech announced plans to migrate its supercomputer to the Xserve G5 in January, just months after it was built. The university has subsequently dismantled its original system, which was based on the desktop Power Mac G5 system, Grossman said.

The Xserve G5 met with some shipping delays earlier this year, but the dual processor systems that Virginia Tech plans to use have been shipping in volume since April, Grossman said.

"We have a lot more customers to come that will be on the Top500 list, we believe," Grossman said.

One such customer will be Colsa, which expects to run the Top500's Linpack benchmark on the MACH 5 in time for the November list, according to Antony DiRienzo, executive vice president at Colsa. Colsa will take its first truckload of 300 dual-processor Xserve G5 systems next week, DiRienzo said.

The IDG News Service is a Network World affiliate.