Blue Gene/P is three times more potent than the current fastest machine, BlueGene/L, also built by IBM.
The latest number cruncher is capable of operating at so called "petaflop" speeds - the equivalent of 1,000 trillion calculations per second.
Approximately 100,000 times more powerful than a PC, the first machine has been bought by the US government.
It will be installed at the Department of Energy's (DOE) Argonne National Laboratory in Illinois later this year.
Two further machines are planned for US laboratories and a fourth has been bought by the UK Science and Technology Facilities Council for its Daresbury Laboratory Cheshire.
The ultra powerful machines will be used for complex simulations to study everything from particle physics to nanotechnology.
Currently the most powerful machine is Blue Gene/L, housed at the Lawrence Livermore National Laboratory in California.
Used to ensure that the US nuclear weapons stockpile remains safe and reliable, it has achieved 280.6 teraflops or trillions of calculations per second.
The machine packs 131,072 processors and is theoretically capable of reaching 367 teraflops.
By comparison the standard one petaflop Blue Gene/P comes with 294,912-processors connected by a high-speed, optical network.
However, it can be expanded to pack 884,736 processors, a configuration that would allow the machine to compute 3,000 trillion calculations per second (three petaflops).
"Blue Gene/P marks the evolution of the most powerful supercomputing platform the world has ever known," said Dave Turek, vice president of deep computing, IBM.
The new Blue Gene computers form just a part of IBM's supercomputing portfolio.
The world's biggest computer-services company has built almost half of the 500 fastest supercomputers.
It is also currently building a bespoke supercomputer for the DOE's Los Alamos National Laboratory, New Mexico.
Codenamed Roadrunner, it will be able to crunch through 1.6 thousand trillion calculations per second.
The computer will contain 16,000 standard processors working alongside 16,000 "cell" processors, designed for the PlayStation 3 (PS3).
Each cell chip consists of eight processors controlled by a master unit that can assign tasks to each member of the processing team. Each cell is capable of 256 billion calculations per second.
The power of the cell chip means Roadrunner needs far fewer processors than its predecessors.
Another contender for top supercomputer has been unveiled by Sun. Its Constellation machine will be able to run at a maximum speed of 1.7 petaflops.
The first Constellation machine, called Ranger, is being put together for the University of Texas at Austin and will run at a modest 500 teraflops.