Moore's law is alive and kicking

LAST YEAR was the 40th anniversary of Moore's Law, Intel founder Gordon Moore's prediction that the number of transistors on a chip would double about every two years.

A lot of learned researchers have since explained why Moore's Law was ending. And yet, it hasn't. Boyd Davis, general manager of Intel's Server Platforms Group Marketing, says, "It's still actually physically possible to make faster chips. It just becomes difficult to take heat away from the silicon, and there are diminishing returns on speed."

So instead, the physical limits being hit are cooling and energy consumption. Hence the shift to multithreading and multi-cores which in turn are driving a shift in software design towards code whose workload can be split into chunks for parallel processing. For this, digital media is a natural.

"We have gone through a major shift in terms of where we invest in Moore's Law." Intel previewed its forthcoming quad-core Xeons at last week's Intel Developer Forum.

"It's a huge trend. It came pretty quickly, led by a lot of factors." For one: the needs of data centres. "Following the dot-com meltdown, a lot of companies consolidated their data centres, for example going from 20 to three. Many companies now have much larger, but fewer data centres. And then suddenly as their compute needs grew, they found they were getting more and more crowded, and there were physical constraints as to how much electricity you could get in and how much heat you could take out. There's an industry saying - the most expensive server purchase is the one that forces you to build another data centre." Quad-core, he says, will need 80 watts, only 15 watts more than dual-core, which itself offered triple the performance per watt of the previous generation.

The second megatrend Davis talks about is the arrival of virtualisation as a mainstream technology, allowing multiple environments and applications to run on the same system.

"Both of those are areas where we're very heavily invested."

Earlier this year, many media outlets were discussing what Intel had to do to beat AMD. Now, with quad-core products due to appear in November, Davis believes Intel has a "sizeable time-to-market lead", and believes the line-up that's being brought out is reinstating Intel's lead.

Yet, he doesn't believe anything particular had to change to make that possible. "We have relatively long design cycles. It's not like we woke up in the second half of 2005 with our competitor beating us on benchmarks. We obviously have built a product strategy and road map over a multiyear horizon. The shift that we had made to go from architecture optimised for clock speed to architecture optimised for energy efficient performance - we had a window where our products didn't necessarily win on all the benchamrks. Clearly the more competition you face as a company the more you're going to be on your sharpest edge. But I don't think anything fundamentally changed."

The company did need to make a significant technical advance for quad-core, though: it had to be able to transition to 65 nanometer lithography generation. Being able to build in high volumes was, he says, the most fundamental breakthrough. And so Moore's Law continues. "There probably will be limits at some point, but they'll be practical: who wants to build systems that are very expensive for minimal performance gains? Whereas, there are huge benefits from shifting to more cores, more threads, and the ability to run software more in parallel."

We haven't yet, he says, reached the point where computers need no more speed. "I've been in this business for 16 years, and from the day I started there have been people who thought computers didn't need to go faster because they did mostly what customers wanted them to do. It's been the argument since virtually the dawn of computers." The next driver, Davis believes, is consumers' increasing expectations of high-definition digital media.

"We believe Moore's Law is alive and well, and as healthy as it's ever been." µ

Wendy M. Grossman's Web site has an extensive archive of her books, articles, and music, and a page linking to in this series. Readers are welcome to send email to netwars@skeptic.demon.co.uk (but please turn off HTML).