Advanced Micro Devices gained share in worldwide processor shipments at the expense of arch-rival Intel during the fourth quarter of 2009, according to new research.

AMD shipped 19.4 percent of the world microprocessors, according to IDC, marking an increase from 17.7 percent the previous year. Although Intel maintained its dominant overall position, shipping 80.5 percent of all processors, it slipped from the 81.9 percent seen the previous year.

Sunnyvale Calif.-based AMD was able to gain on in both the laptop in desktop categories.

Intel suffered a blow in the beginning of the year when its Atom processor -- typically powering less powerful laptops-- plummeted. Aggressive pricing on AMD's part helped it capitalize, according to Shane Rau, research director at IDC. New products also helped the chip company.

In September AMD introduced newer and faster laptop processors belonging to the Turion II X2 and Athlon lines. The processors were part of platforms that delivered improved graphics capabilities and energy efficiency.

In the end Intel's laptop processor share dropped to 87.3 percent compared to 89.1 percent the previous year.

AMD also recorded gains in the desktop processor market, with its market share up to 28.6 percent from 26 percent last year. Intel's market share dropped to 71.1 percent from the 73.9 percent share it had a year ago.

Intel isn't sitting around however. It recently refreshed its line of laptop and desktop processors, launching new power-efficient chips that deliver more performance and newer features.

Overall, worldwide processor demand achieved all-time record levels for a single quarter, IDC said.

Microprocessor shipments went up by 31.3 percent in the fourth quarter of 2009 compared to the same quarter in 2008.

Compared to 4Q08, the huge rise in shipments indicates that the market has put the recession behind it, Rau said. Both comparisons indicate that the PC industry anticipates improvement in PC end demand in 2010.

Meanwhile, the third player in the x86 microprocessor market, Via Technologies, recorded a drop in market share. The company held a 0.1 percent share, compared to 0.4 percent in the fourth quarter of 2008.

Intel