[Omah]

http://www.bbc.co.uk/news/technology-18457716

IBM's Sequoia has taken the top spot on the list of the world's fastest supercomputers for the US.

The newly installed system trumped Japan's K Computer made by Fujitsu which fell to second place.

It is the first time the US can claim pole position since it was beaten by China two years ago.

Sequoia will be used to carry out simulations to help extend the life of aging nuclear weapons, avoiding the need for real-world underground tests.

It is installed at the US Department of Energy's Lawrence Livermore National Laboratory in California.

The computer is capable of calculating in one hour what otherwise would take 6.7 billion people using hand calculators 320 years to complete if they worked non-stop.

Sequoia is 1.55 times faster than the Fujitsu model, and uses over 1.5 million processors.

In comparison the Japanese model has less than half the number of CPUs (central processing units).

The IBM supercomputer is also more energy efficient than the Fujitsu model.

Sequoia consumes 7.9 megawatts compared to the K computer which uses 12.6 megawatts.

The first computer to take the top position on the list was the CM-5/1024 in 1993, designed by Thinking Machines.

According to Prof Dongarra, Sequoia is 273,930 times faster.

"A calculation that took three full days to compute on the Thinking Machines in 1993 today can be done in less than one second on the Sequoia," he said.

Presumably the Prof uses it for completing his tax return .....