The p655 eServer can be rack mounted but when 16 units are loaded onto a 6ft rack, the total weight is 3,600lbs (1,633kg) - or about 2tons.
This may mean hidden costs for floor strengthening but, because of the lower heat output of each module, the floorspace required is reduced to one-sixth of Hewlett-Packard's rx5670.
HP is IBM's main competitor in this field. The battle is between the Intel Itanium 2 chips used by HP and the Power4 processor from IBM.
Although the high-performance computing market is a relatively small space, the prestige it carries is massive with Hewlett-Packard, IBM, SGI/Cray and Hitachi all fighting for the computer power laurels and the attention that brings.
Each p655 module can take four or eight Power4 processors which racks up 128 processors in a fully populated tower to give a peak performance of half a trillion operations per second. The servers are clustered together using eServer Cluster 1600 and can run Linux or Aix 5L Unix.
The new pSeries server has been developed as the basis of the next generation of supercomputer that started with Deep Blue, the computer that defeated chess grandmaster Gary Kasparov.
Typical applications would be in pharmaceutical and life science genome research or in the petrochemical industry.
At the low end, a basic p655 module with four-processor capacity, 4Gbytes memory and 218Gbytes storage costs £57,359, which means prices for the full stack can reach well over £1m.
This price is dwarfed by the $290m (£185m) for two supercomputers ordered from IBM by the US government. The main order is for an ASCI Purple computer which runs at 100 teraflops per second, equivalent to the speed of the human brain, IBM claims.
This restores IBM's lead in the supercomputer race from NEC's Earth-Simulator/5120 which performs at 40 teraflops per second.
The other IBM order is for an even faster machine, Blue Gene/L, which is expected to run at 360 teraflops per second when it is completed in 2005.