Intel's P6 chip architecture not dead yet

Banias, a low-power chip for notebooks and Internet devices coming from Intel in the first half of 2003, will be based around the P6 architecture, the processor design that is being phased out in other Intel product lines, according to Kevin Krewell, an analyst at subscription newsletter "Microprocessor Report." The chip will contain significant new modifications for saving power but will effectively feature the same computing core as the Pentium Pro, which debuted in 1996.

"The P6 architecture in this morphed version will live on," he said during a seminar at the Microprocessor Forum here on Monday. "Banias is a derivative of the Pentium III, we know that."

An Intel representative would not comment directly on the matter but said that Banias would be a "derivative" of Intel's overall processor technology.

The adoption of the P6 architecture for Banias is interesting on a number of levels. One, it shows the resiliency of the design. The P6 architecture emerged with the Pentium Pro, a server chip, and was adapted to the Pentium II, the Pentium III, the Celeron family and Xeon server chips.

The Pentium 4 is based on the P7 architecture, which is becoming Intel's main chip design. Right now, the P7 architecture is used in desktop chips and a few members of the Xeon family, but it will appear in notebooks and the Celeron line next year. Intel has already said it will phase out the Pentium III on desktops by the end of the year.

The P7 and P6 architectures are related. Both are members of the overall X86 family. Internally, however, the chips are quite different. Processors based on the P7 design, for example, contain enhanced circuitry for streaming media and have more processing circuitry in general.

The P6 plans also partly show how Intel intends to get around some of the power consumption issues involved with marketing chips for devices and small notebooks. The Pentium 4 provides substantially more performance than the Pentium III. Unfortunately, it also consumes a lot of energy. To date, Intel has been relatively vague when it comes to details on the underlying technology behind Banias.

"It is very difficult to get the Pentium 4 into thin-and-light notebooks," said Nathan Brookwood, an analyst at Insight 64.

Even though the Pentium 4 will come to notebooks next year, it may largely be used in the "desktop replacement" category of notebooks--models weighing seven to eight pounds that are losing market ground to more portable machines. Lightweight notebooks will likely continue to use Pentium IIIs through 2002, Brookwood predicted.

Power consumption is one of the main issues facing processor manufacturers. As chip speed increases, power consumption grows, which, if left unchecked, leads to lower battery life and dangerous heat buildup.

Transmeta, IBM and Intel will all discuss power consumption this week at the Microprocessor Forum, a five-day conference dedicated to processor design.

Banias, of course, will contain technology not found on current Pentium IIIs. One feature will fuse micro-operations, necessary tasks that currently require processing the same calculations repetitively. By fusing these operations, Banias will cut down the number of separate calculations performed by the chip, conserving energy. Additionally, Banias will automatically shut off subsections of the processor when not in use to save power.

The chip could also contain elements from the P7 architecture from the Pentium 4. The Pentium 4, for instance, has a much faster bus, the main data path between the processor and memory, than the Pentium III. By grafting the Pentium 4 bus on a Pentium III chip, Intel could "have the best of both worlds," speculated Brookwood.

"The Pentium III is very good (in low-power notebooks), but the Pentium III is clearly constrained by its ability to move data in and out of the processor," he added.