Personal desktop computers using AMD's next-generation Athlon XP microprocessor, known as Clawhammer, will now be available late in the first quarter of 2003 or early in the second quarter of 2003.

John Crank, a senior branding associate for Sunnyvale, California-based AMD, declined to specify the reason for the delay.

"It simply reflects a change in the roadmap, which is a flexible document," Crank said.

Microprocessors are the "brains" of a personal computer.

The timetable for AMD's version of the chip for server computers, known as Opteron, is unchanged and is on course to be introduced in the first half of next year, Crank said.

AMD, Intel Corp.'s INTC.O principal rival in the microprocessor market, also said it was delaying the commercial release of an Athlon chip, code-named Barton, until the first quarter of 2003, from the second half of this year.

AMD cited its decision to increase that chip's data pathway, the freeway on the processor linking it to other parts of the computer.

AMD said the Barton chip will boast a front-side bus, the data freeway, running at 333 megahertz, compared with 266 megahertz currently. It will also have 512 kilobytes of memory on the chip, double what Athlon chips now have.