IBM has snatched the supercomputing crown, helped by two unusual prototypes.
It is the first time the Blue Gene prototypes have made the top 10
The tech giant has the most machines in the Top 500 list of supercomputers, accounting for 224 of the world's fastest machines.
They include two prototypes in the top 10, the Blue Gene/L systems, which use far less space and power than more traditional supercomputers.
But the Earth Simulator supercomputer, by NEC in Japan, remains number one.
The Top 500 list is published every six months and is based on a mathematical speed test called Linpack which measures the number of calculations per second.
In the latest list just published, IBM machines make up just under 50% of all the systems on the list. Hewlett-Packard came second with 28% of systems.
Among its supercomputers are the Blue Gene prototypes which have made it into the top 10 for the first time.
The Blue Gene/L systems use far less space and power than traditional supercomputers. These are usually made up of vast racks of machinery, which could fill a football pitch. By comparison, the IBM prototypes are the size of several fridges.
The machines were originally built as part of a research project to study the biological process of protein-folding.
TOP 10 SUPERCOMPUTERS
1: Earth Simulator Center, Japan
2: Intel Itanium2 Tiger4 1.4GHz, Quadrics
3: ASCI Q - AlphaServer SC45, 1.25 GHz
4: BlueGene/L DD1 Prototype (0.5GHz PowerPC 440 w/Custom)
5: PowerEdge 1750, P4 Xeon 3.06 GHz, Myrinet
6: eServer pSeries 690 (1.9 GHz Power4+)
7: Riken Super Combined Cluster
8: BlueGene/L DD2 Prototype (0.7 GHz PowerPC 440)
9: Integrity rx2600 Itanium2 1.5 GHz, Quadrics
10: Dawning 4000A, Opteron 2.2 GHz, Myrinet
Now IBM is planning to turn the prototypes into a commercial product which it says will make supercomputing far more accessible to business and research institutions.
The tech giant foresees machines that can fit under a desk and require a fraction of the power of traditional supercomputers.
Analyst firm IDC expects the supercomputer market to expand by 6.5% a year, from $5.6bn last year to $7.6bn by 2008.
"Whether we are talking about improving the accuracy of weather forecasts, designing better automobiles or improving disease research, we are seeing the advent of a new supercomputing age," said Dave Turek, vice president of Deep Computing at IBM.
The Blue Gene/L machine ranked fourth has a sustained speed of 11.68 teraflops and a peak speed of 16 teraflops. It uses more than 8,000 PowerPC processors packed into just four refrigerator-sized racks.
The eighth-ranked prototype has a sustained speed of 8.66 teraflops and a peak speed of 11.47 teraflops.
IBM is building a Blue Gene machine for the Lawrence Livermore National Laboratory in the US, which should be up and running next year.
The supercomputer is predicted to be nine times as fast and about a tenth the size of the fastest machine today, the NEC Earth Simulator, dedicated to climate modelling and simulating seismic activity.
The Top 500 list is compiled by a group of computer science academics from around the world.