Intel and AMD are racing to introduce a dual-core computer chip in what could be the biggest change in PC technology in a decade.

Both companies have something to prove, and both expect in a matter of months to launch products that essentially combine two microchips into one.

For Intel, the transition offers a chance to shake off a year's worth of missteps and delays with an on-time product introduction. For AMD, the change amounts to its best opportunity in years to take business away from Intel, its much larger rival.

Having approached the limits of speed gains with traditional chips, Intel and AMD have moved to combine two chips onto a single piece of silicon.

The result is one chip with two cores that can operate independently -- with one, for instance, allowing users to view a television show while the other scans for viruses.

For some applications, such as the multimedia processing that is seen as a key path for PC industry growth, dual core shows major gains. "On some benchmarks, it just blows everything away," said Gartner analyst Martin Reynolds.

Intel generally keeps reviews under wraps until it launches a chip with PC partners. Yet the company recently turned heads in the computer industry by allowing independent reviewers to publish performance tests on its first dual-core computer chip, called Extreme Edition, before it becomes officially available. The reviews were generally positive, though some noted the chip's high heat production.

Yesterday, Intel President Paul Otellini announced in Washington that the dual-core chips would become available next month, within the previously announced second-quarter time frame, said spokeswoman Laura Anderson.

AMD, which has set a "midyear" target release for its dual-core chips, is dropping hints that the product may arrive sooner. It has told the media to expect important news at a New York event on 21 April to mark the two-year anniversary of its Opteron chip for business PCs, known as servers.

Opteron has not rescued AMD's market share, despite a major push. AMD's share of the market for PC microprocessors dipped nearly a percentage point last year to 15.7 per cent, while Intel gained a point to 81.5 per cent, IDC figures show.

'Coke and Pepsi'
But it would take a persistent marketing effort and flawless manufacturing for either company to steal business from the other, said RBC Capital Markets analyst Apjit Walia. "It's a lot like Coke and Pepsi," he said. "It has less to do with taste. It's branding and execution."

Last year, both Intel and AMD accelerated plans to switch to dual-core products for their Pentium and Athlon brands of microprocessors, the central chips in PCs.

The speed gains made throughout the 1990s had begun to slow, and it became clear that the next big advance would be in multiprocessing: giving PCs the equivalent of more than one brain to better handle more than one process at a time.

In the end, both companies are likely to introduce their dual-core chips within a few weeks or months of each other. The chips, however, will initially target different markets.

Intel's Pentium D and Pentium Extreme Edition will be used in desktop computers; AMD's dual-core Opteron chip will target servers. Then, through 2006, the companies will broaden their dual-core lines into all the major PC markets: mobile, desktop and server.

"Every enthusiast out there has been waiting for this for years," said Nathan Kirsch, editor in chief of Legit Reviews, a Web site that reviews computer components and chips.

Walia said he believes AMD will have trouble taking business from Intel during the dual-core transition, even if they have a better chip.

"AMD has many times proven that they have possibly a better technology," he said. "But when it comes to execution, it's always been that Intel's managed to execute better and still retain if not gain share."

"This is the same scenario that's been played out for almost a decade now," he said.