Advanced Micro Devices (NYSE: AMD) took an early lead against rival Intel Corp. (NASDAQ: INTC) in the 64-bit mobile computer market last year. However new data released today shows that Intel grabbed the lead in December, becoming the top 64-bit CPU provider in only four months.

Sales figures for notebook chip from market researcher Current Analysis show that Intel’s Core 2 Duo mobile processors took the 64-bit lead with a 24 percent market share compared to AMD’s Turion 64 X2 chips, which slipped to third place with a 20 percent market share. In second place is Intel’s own Celeron line of 32-bit processors with a 21 percent share.

AMD’s 64-bit troubles come after the firm reported a 2006 fourth quarter net loss of $574 million on Tuesday on slower sales as a result of a fierce price war with Intel in addition to a costly $5.4 billion purchase of video graphics chip maker ATI Technologies, Inc., for which the company took a $540 million charge.

AMD was first to market in 64-bit computing in July last year, with the release of the Turion 64 X2 chips. This advantage allowed AMD to gain significant market share in the segment and even maintain its advantage after Intel's own 64-bit processor was released in July.

Its is expected that growth of the Intel Core 2 Duo processor will continue in 2007 with the recent announcement of Intel’s addition of 802.11n wireless cards to its products lines and the slow but increasing awareness of 64-bit computing and the availability of 64-bit versions of the upcoming Vista operating system., Current Analysis researcher Hans Casto noted.

More computers are emerging with the ability to support 64-bit operations, making computers that can compute more data than previously possible.

Shares of AMD rose 17 cents, or 1.06 percent, to close at $16.22 on Friday on the New York Stock Exchange.