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In today's computers, energy efficiency trumps speed

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American



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Fifty years ago this month, inventor Robert Noyce created the first planar integrated circuit made from silicon—an innovation that allowed multiple transistors to be placed on the same microprocessor and paved the way for the development of ever smaller and more powerful electronics. Silicon Valley pioneer Intel Corp., co-founded in 1968 by Noyce  and fellow inventor Gordon Moore in Santa Clara, Calif., today hosted a confab in New York City highlighting the company's role in developing faster, more powerful and greener electronics used to make tomorrow's computers.

Over the past few years, particularly as battery-powered mobile devices have proliferated, energy efficiency has replaced clock speed as the main measure of a computer processor's worth, Sean Koehl, an Intel technology evangelist, said at today's event. To build faster processors that don't use more electricity, Intel, as well as fellow chipmakers Advanced Micro Devices, Inc. (AMD) and NVIDIA Corp., have focused on increasing the amount of data that can be processed in parallel akin to opening additional toll booths on a busy highway to keep traffic flowing.

Instead of tollbooths, though, Intel and other manufacturers have increased the number of "cores" (which each contain a calculation engine and local memory) on  their chips.  A typical PC sold today has two or four processing cores, but Intel is now working on a new architecture for graphics processing units (GPU), a lightning-fast processor used to deliver sharp graphics. The architecture, dubbed "Larrabee," will be "based on more cores than any processor we've ever released," Koehl said. Products made using this architecture are expected to hit the market later this year or early in 2010.

Koehl expects Larrabee to greatly improve computer graphics, particularly for video games. One example will be more detailed "ray tracing," a technique used to create graphics that resemble photographic 3D images that appear to reflect light and cast shadows. Such detail requires a lot of computer processing power and is difficult to produce in real time (which a video game would demand).

Koehl noted that energy efficiency (while performing such data-intensive tasks) has become a key selling point for consumers in the market for computers and even mobile phones. Instead of asking how many math operations per second a chip can perform, he says, many computer buyers will ask:  "How much can the processor do using a certain amount of watts"?

Image depicting two dies inside Intel's Core 2 Extreme quad-core processor © Intel Corp.

Computer-generated ray-traced image of steel balls © Greg L

Larry Greenemeier is the associate editor of technology for Scientific American, covering a variety of tech-related topics, including biotech, computers, military tech, nanotech and robots.

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