IBM chip is fastest on Earth Water-cooled Power6 is designed for use on big, high-end machines

IBM Corp. began shipping high-end computers Tuesday built around the fastest chip on Earth, a microprocessor that can carry out up to 5 billion instructions per second, surpassing the speediest competing processors built by rivals like Intel or Sun Microsystems.

The new IBM processor, called the Power6, was designed to run big-ticket, water-cooled machines that drive corporations or tackle scientific problems, but slower versions of this same family of chips are already being used in inexpensive, consumer devices like the Nintendo Wii, Microsoft Xbox and Sony PlayStation.

Cranking up the speed is only one way to improve overall system performance, say chip experts from Intel and Sun, which have evolved different ways to coax more work from chips - and therefore stay competitive in the never-ending race to sell computers that do more and cost less.

But if a stopwatch were the only ranking system, the 5-billion-instructions-per second Power6 processor from IBM would beat such rivals as the 3.73 gigahertz Pentium Extreme and the 2.4 gigahertz UltraSparc T2 from Sun.

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"It's hard to make the average person understand just how fast this is," said IBM Chief Technology Officer Bernard Meyerson, offering an example meant to explain his company's baby that still leaves the listener awed with the speediness of the two "laggards."

"Hold your index finger out in front of your face," Meyerson said in a telephone interview from IBM headquarters in New York. In less time than it would take a beam of light to travel from your knuckle to your fingertip, the new IBM chip would complete one task and start looking for the next, he said.

Light would presumably have to travel more than a finger's length to get each task done on the slower processors from Intel and Sun - and at billions-of-cycles per second, slow is a bit of a misnomer.

Then why don't Intel and Sun just crank up the speed? Well, just as is the case with cars, the faster chips run, the hotter they get, and IBM has created water-cooling systems akin to the radiators in cars to keep its processors from overheating. Not doing so, Meyerson quipped, "results in setting fire to the user, which is bad."

Intel spokesman George Alfs said his company, which sells millions upon millions of processors for all sorts of stuff like laptops, where lugging around a water jug would be a chore, said there's no technical reason why Intel chips can't run faster.

In fact, Alfs said, sophisticated game enthusiasts buy water-cooling kits that they fit into desktop PCs, then use software tricks inside the Windows operating system to crank up their own speeds into the 5 gigahertz range.

"But that can void your warranty," Alfs said.

Sun spokesman Mark Richardson took umbrage at the focus on speed. "It's an easier marketing message to deliver to say that faster gigahertz means a faster processor," he said. His colleague, chip expert Fadi Azhari, explained how the Mountain View firm uses a different technical trick, called multithreading, to make a computer faster but not hotter.

Imagine a long line of airport passengers waiting for the ticket agent to check them in, Azhari said. The IBM speed trick would have that ticket agent working faster and faster - with maybe a blower overhead to cool the agent down. But multithreading would be like putting two or more ticket agents on duty, which is another less-heat-intensive approach to processing, he said.