Intel Corp. (INTC) said Tuesday it is combining its desktop and notebook microprocessor architectures, as the world's largest chipmaker focuses on boosting the power efficiency of its chips.

The move is the latest as Intel shifts its focus from making chips that run at ever higher clock speeds, which are now measured in gigahertz, to making chips that have a higher performance per watt.

Such performance is key for small, mobile devices as well as computers in data centers eager to cram more chips into smaller spaces.

The shift in Intel's entire chip development to focus more on power consumption comes as it faces the stiffest-ever competition from its smaller rival, Advanced Micro Devices Inc.(AMD).

Intel also plans to start selling three new versions of lower-power-consuming chips in the second half of 2006, said Intel President and Chief Operating Officer Paul Otellini (search) at Intel Developer Forum, a technology conference.

The chips code-named Woodcrest (search) will be aimed at the computer server market, those code-named Conroe will be aimed at the desktop PC market, and Merom is designed for the notebook PC market, Otellini said. All will be made using Intel's 65 nanometer process technology.

The chips that Otellini announced Tuesday are so-called x86 chips, which are industry standard microprocessors, which are the brains of PCs. They are also dual-core chips, which essentially means two chips in one.

The chips will be able to handle 64 bits of data at once, twice the current standard of x86 chips, which is 32 bits.

"They give us the next level of performance per watt," Otellini said.

Otellini made no immediate mention of Itanium (search), a line of high-end processors for which Intel had high hopes when it was first announced. Intel has invested billions of dollars in its development, but so far the sales of Itanium have been less than what Intel had initially hoped for.

He said after his speech that Intel would outline more Itanium plans Wednesday.

AMD has had considerable success with its Opteron (search) microprocessor, and beat Intel to market with its own dual-core processor. AMD also beat Intel to market with a 64-bit version of Opteron.