Intel powers up plans for low-power chips

The chip giant showed off road maps for its server, notebook and desktop chips for 2006 and 2007 at its Intel Developer Forum here Tuesday, and the dominant theme revolves around reducing power consumption, a concept the company has espoused since the beginning of the decade.

Some of the future chips also reverse key technological decisions and design ideas behind the Pentium 4. Hyperthreading, one of the touted features of the Pentium 4, will not be part of a new round of chips coming in the second half of 2006, although later chips will likely include some form of threading.

"NetBurst (the architecture behind the Pentium 4) is dead," said Kevin Krewell, editor in chief of the Microprocessor Report.

Merom, a notebook chip coming in the second half of 2006, is expected to provide substantially more performance than current notebook chips, though Intel did not reveal how much power it would consume. An unnamed chip coming a few years later is expected to consume a maximum of 5 watts of power, and an ultra-low-voltage version, 0.5 watt. Current Pentium M chips for notebooks consume a maximum of about 27 watts, while ultra-low-voltage Pentium Ms demand 5.5 watts.

Conroe, a desktop relative of Merom coming out at the same time, will consume a maximum of 65 watts. Current Pentium 4s consume close to 95 watts. In servers, Woodcrest will consume a maximum of 80 watts, far less than the 110-watt maximum of today's Xeon processors.

Toward the end of the decade, Intel will also come out with an ultra-low-power version of its chip for consumer electronics that consumes one-tenth of the power of chips like Merom, Intel CEO Paul Otellini said during an IDF keynote speech.

Lower power consumption is important to PC and handheld makers as chips get ever more powerful. It gives them the flexibility to build, at one end of the scale, systems with significantly greater performance than existing designs, or at the other end, systems that consume far less energy. That latter factor is key for coming generations of cell phones and other small, portable systems.

Streamlined pipelines
The new architecture behind Merom, Conroe and Woodcrest contains a number of technological enhancements, but it also harks back to earlier designs. The chips will have a 14-stage pipeline, said Steve Smith, vice president of intel's digital enterprise group. The pipeline is like a chip's assembly line. More stages allow a chip to run at faster speeds but also mean greater power consumption.

While Pentium II and III chips had similar-size pipelines, the Pentium 4 had a 20-stage pipeline when it debuted and later chips had 31 stages. Many analysts blamed the Pentium 4's power consumption problems in part on the long pipeline.

The chips will also not include hyperthreading, which lets a single core perform more than one task at once, to cut power consumption, Smith said. He added, however, that threading may be added in future versions of chips based on this architecture.

Smith also said that the cores on these chips will share a single cache, similar to IBM's Power 4 dual-core chips. AMD's and Intel's current dual-core chips have separate caches.

Additionally, the chips will come with an improved out-of-order execution unit, which improves performance by allowing a chip to finish tasks without having to wait until other calculations are complete.

Unlike AMD's Opteron processors, none of Intel's forthcoming chips comes with an integrated memory controller, which many analysts say can improve performance. The company said it wanted to tackle the conversion of the architecture first. In future chips, it may integrate memory controllers, which let the processor get data from memory.

The new architecture does not have a name. "We deliberately did not name it," Otellini said. The architecture behind the Pentium 4 is known as NetBurst, and Intel declared at its launch that it would last a decade. NetBurst, however, is being phased out after six years.

Other road map details go as follows:

• Servers: As earlier announced, Intel will come out with a dual-core server chip, code-named Paxville, later this year. The initial version of Paxville will fit into two-processor servers. A version for servers with four or more will come out in 2006, Smith said.

In the second half of 2006, Tulsa, for four-processor servers, will debut along with Woodcrest. Then in 2007, Whitefield, Intel's first four-core processor, will come out. Whitefield is being designed in the company's labs in Bangalore.

• Desktops: Presler, a chip out of the Pentium 4 line, will appear in the first half of 2006, while Conroe will follow in the second half. Two PC platforms, or blueprints, are being prepped for Conroe: Averill, for corporate computers, and Bridge Creek, for home computers.

For value desktops, Intel will release Cedar Mill in the second half. Although over 90 percent of Intel chips will sport two cores by 2007, single-core chips like Cedar Mill will still be around. These sort of chips cost less to make.

"We expect single-core processors to exist for quite some time in our value processor line," Smith said.

• Notebooks: Yonah, a new notebook chip, will appear in the first part of 2006, before Merom.