The BlueGene/L System, jointly developed by IBM and the U.S. Department of Energy, remains the world's fastest supercomputer, topping the latest biannual list that saw five new entrants into the top 10.

The BlueGene/L System has held the No. 1 spot since November 2004. The latest list of top 500 computers was released Monday at SC07, the international conference on high-performance computing in Reno, Nev.

The current IBM system has been significantly expanded, achieving a Linpack benchmark performance of 478.2 teraflops. A teraflop (TFlop/s) equals a trillion calculations per second. Six months ago, the BlueGene held the top position with 280.6 TFlop/s.

Making its first entry in the Top 10 was a newer version of the same type of IBM system. The BlueGene/P system, called Jugene, debuted at No. 2 with a performance of 167.3 TFlop/s. The system is installed at the German computer research center Forschungszentrum Juelich.

Another new system made its debut in the No. 3 spot. The supercomputer at the New Mexico Computer Applications Center in Rio Rancho was built by SGI and based on the Altix ICE 8200 model. The system posted a speed of 126.9 TFlop/s.

India placed a system for the first time in the top 10. The Hewlett-Packard Cluster Platform 3000 BL460c system was No. 4 at a speed of 117.9 TFlop/s. The system was installed at the Computational Research Laboratories, a subsidiary of Tata Sons Ltd. in Pune, India.

The No. 5 system was also a new HP Cluster Platform 3000 BL460c system, which was installed at a Swedish government agency. The system's speed reached 102.8 TFlop/s.

The last new system in the Top 10 was the Cray XT4 system installed at the National Energy Research Scientific Computing Center at the DOE's Lawrence Berkeley National Laboratory. The system, called Franklin, came in at No. 9 with a performance of 85.4 TFlop/s.

Rounding out the top 10 systems was the Sandia/Cray Red Storm at the NNSA/Sandia National Laboratories in Albuquerque, N.M. The Cray system was No. 6 at 102.2 TFlop/s.

No. 7 at 101.7 TFlop/s was the Cray XT4/XT3 system, called Jaguar, at the Oak Ridge National Laboratory in Tennessee. Following the Cray system was IBM's eServer Blue Gene at the IBM Thomas J. Watson Research Center, Yorktown Heights, N.Y., where it achieved 91.29 TFlop/s.

Finally, No. 10 was an eServer Blue Gene system, called New York Blue, at the Stony Brook/BNL, New York Center for Computational Services. The IBM system measured 82.161 TFlop/s.

The complete list of the world's top 500 super computers is available on the SC07's Website. The current list is the 30th edition of the closely watched ranking.