The Department of Energy's Oak Ridge, Tenn., National Laboratory has boosted the computing power of its Cray XT Jaguar supercomputer to more than a quadrillion mathematical calculations per second, surpassing the IBM Roadrunner, which topped the list of the world's 500 fastest computers in June.

The beefed-up Jaguar has a peak performance of 1.64 petaflops, compared with the Roadrunner's 1.026 petaflops. The Roadrunner is used for nuclear security and scientific research at the Los Alamos National Laboratory.

A spokesman for the Oak Ridge lab, however, said Monday the laboratory is not calling its system the world's fastest computer. The official list compiled by university and government scientists twice a year is scheduled to be released next week.

The upgraded Jaguar already has been used by scientists to complete a superconductivity calculation that required a sustained performance of more than 1.3 petaflops. Superconductivity is a phenomenon characterized by exactly zero electrical resistance. The phenomenon occurs in certain materials generally at very low temperatures.

Raymond L. Orbach, the DOE's undersecretary for science, said the faster Jaguar would enable researchers to simulate physical processes on a scale "never seen before."

"High-end computation will become the critical third pillar for scientific discovery, along with experiment and theory," Orbach said in a statement.

The DOE started the Jaguar upgrade four years ago in an effort to offer more computing power for unclassified research. The federal agency claims the project was completed on time and on budget and exceeded the original scope.

"The new petaflops machine will make it possible to address some of the most challenging scientific problems in areas such as climate modeling, renewable energy, materials science, fusion, and combustion," said Michael Strayer, associate director of the DOE Office of Science for Advanced Scientific Computing Research.

The faster Jaguar is expected to be a boon for U.S. industry by making it possible to perform "virtual prototyping" of complex systems and products. Such prototyping reduces development costs and shortens the time required to market new technologies, the DOE said.

Jaguar is the result of a partnership between the DOE, the Oak Ridge lab, and supercomputer vendor Cray. The upgrade was accomplished by adding 200 cabinets of Cray's XT5, a Linux-based supercomputer that uses quad-core Opteron processors from Advanced Micro Devices. The older Jaguar used 84 cabinets.

The new system uses more than 45,000 Opteron processors and features 362 TB of memory and a 10-PB file system. The machine has 578 TB per second of memory bandwidth and an input/output bandwidth of 284 GB per second. The latter tackles the biggest bottleneck in supercomputers, which is moving data into and out of processors.

The upgraded Jaguar will undergo testing in late December before moving to production in early 2009.