• PC World
• »Components
• »Processors

Intel will introduce its new Dothan mobile processor at a launch event in San Francisco on May 10, the chip maker says.

Dothan is the code name for the 90-nanometer version of the Pentium M processor, introduced last year under the code name Banias. The Pentium M, along with a mobile chip set and a wireless Internet chip, makes up Intel's Centrino mobile package for notebooks.

With Dothan, Intel is doubling the amount of Level 2 cache that comes with the processor to 2 megabytes. Cache is used to store frequently accessed data close to the processor in order to reduce the time needed to fetch that data and run it through the processor.

With Power, More Heat

The jump to a 90-nanometer process technology enables Intel to decrease the size of the transistors on the chip. This means the company can add transistors to improve performance without having to increase the size of the chip.

Intel has already shipped the Prescott Pentium 4, its first 90-nanometer processor for desktop PCs. That chip actually consumed more power than its Northwood predecessor, and there are some concerns that Dothan might do the same. The additional power consumption could be prompted by the additional cache as well as excess power leakage from chips made on the 90-nanometer process generation.

Power consumption is a much more important consideration for notebook designers since both battery life and mobility are affected by chips that consume excess power.

Anand Chandrasekher, vice president and general manager of Intel's mobile processor business, has said Dothan will provide the same level of battery life as the current Banias Pentium M chips, but with better performance.

An increase in cache size requires more power to feed the additional transistors, but Intel can do several things in its architectural design to better manage that power, says Dean McCarron, principal analyst with Mercury Research.

The Banias Pentium M processor is a good example of well-managed power consumption, and Intel will probably use similar and more-sophisticated techniques to handle the power consumed by Dothan's larger cache and possible current leakage, McCarron says.

Future Appearances

Later this year, Intel will pair Dothan with the Alviso chip set and new dual-band wireless Internet chips to create Sonoma, the code name for the next-generation Centrino platform. Alviso consumes less power than current Intel mobile chip sets, and Sonoma will also include technology to reduce the amount of power consumed by a notebook's display.

Dothan was supposed to launch in the first quarter, but was delayed when the company had to modify some circuits on the chip to ensure it could be manufactured in high volume, Intel President and Chief Operating Officer Paul Otellini said in January.

Dothan will also be the first chip launched since Intel decided in March to adopt a performance-based numbering scheme. All future Pentium M chips will fall into the 700 series. Intel will rate chips based on a number of factors, such as clock speed and cache size.