Off The Clock -- Are The GHz Wars Over?

When Rahul Sood selects processors these days, he's looking for "the closest thing to a 'flux capacitor' as we can get." What's interesting about the Voodoo PC frontman's line is that it appears that a reference to a popular movie from the 1980s has more relevance these days than the clock speed fixation that defined microprocessor shopping much more recently.

Make no mistake. Chip makers, system builders and hardware tweakers have always known that there is a whole lot more that goes into processor performance than just its clock. In the modern era of multi-core chips, GPUs, power concerns and platform integration, optimizing computer performance involves much, much more than slapping the fastest CPU you can find onto a motherboard and calling it a day.

The "megahertz myth" was famously scoffed at by Steve Jobs back in the early 2000s when Apple's PowerPC chips were having, well, their clocks cleaned by Intel's faster parts. Jobs' attitude was surely part marketing spin, but his premise -- that architectural advantages like the PowerPC's shorter pipelines can mean as much or more for performance as raw clock speed -- is now acknowledged as plain common sense by everybody, Intel included.

What's surprising, perhaps, is how quickly and totally this way of thinking about processors has taken hold.

Years ago, breaking the 1GHz barrier was greeted with the gearhead community's version of a ticker-tape parade. Nowadays, even as Intel and Advanced Micro Devices approach the halfway mark to 4GHz -- and baked-in overclocking capabilities and advanced cooling take chips' listed clock speeds hurtling past that barrier -- nobody really seems to care.

"Clock speed is the least important factor these days," said Sood, chief technology officer for Hewlett-Packard's Global Voodoo Business Unit. "What's important is how efficient the CPU is. In other words, lowest power, smallest footprint, lowest thermal requirements and best performance are what we look for when designing a new device."

Will a 4GHz off-the-shelf processor be big news when it arrives?

"Not really, at least not with my circle of friends," he said.

Intel's latest Core i5-670 processor runs with a base speed of 3.46GHz and can get a bump to 3.73GHz via the chip giant's Turbo Boost technology, which in certain conditions dials down processing on some cores and ratchets up the frequency of others on multi-core processors.

That's knocking on the door of 4GHz, but Nor-Tech's Todd Swank thinks the milestone won't much matter to the general public when it arrives.

"I think the 4GHz barrier is an exciting milestone to cross and will be followed by those of us in the industry, but I don't think it will generate nearly as much interest by the general population as when Intel and AMD both battled to surpass the 1Ghz mark," he said.

Swank, vice president of marketing at Burnsville, Minn.-based system builder Nor-Tech, said clock speed is just one of many considerations his customers have.

"It's amazing what's happened with clock speed. It used to be what everyone asked for when buying systems, but now there are just so many other variables to consider," he said. "Nowadays, when customers are giving us specifications, we're just as likely to see any of the following requests instead -- processor brand, model number, core count, onboard cache or features like Intel Turbo Boost."

The "relative weight" of core frequency "is lower than it was a few years ago" when it comes to evaluating processor performance, said Todd Garrigues, Intel's North America channel manager. The upshot for system builders, he said, is that with so much more to talk about with customers, there is much more opportunity to "add value by helping define what performance is" in their particular case.

"Is it getting multiple tasks done simultaneously, getting a single project like video editing done quickly, energy efficiency, etcetera? That is where the channel can step in and have a conversation with their customers, helping them make the best decisions possible," Garrigues said.

Next: More Talk About Clock Speed

Here are some more insights into the importance -- or lack thereof -- of clock speed when evaluating microprocessors:

"Core frequency is one variable when looking at performance, though its relative weight is lower than it was a few years ago. The CPU architecture, thread count, cache memory and efficiency of the architecture itself all have significant impact to overall performance."

-- Todd Garrigues, North America Channel Manager, Intel

"I think it's hard to divine what everybody's looking at for requirements. When you look at trying to get the right processor for the right money, well, processor price has come down so much, that you're even getting four cores in an [AMD] Athlon II that are pretty darn fast. The really important thing to make sure your system is more responsive, more than the clock, is making sure you have four cores."

-- Brent Barry, PC Gaming strategist, AMD

"I find that advertising clock speed is like advertising engine size in a car. It provides an effective shorthand to characterize a product but is often wrongly seen as the one true metric of efficacy. If you don't take the rest of the system into account -- tires, steering, trunk space, stereo -- you're going to have a very unpleasant experience. Besides, nowhere on my commute do I ever see the opportunity to do 185 mph. But it sure is nice to know I have -- admittedly unsexy -- run-flat tires."

-- Kevin Jacoby, CEO, Rain Computers

"We often have to educate customers to not use only clock speed when they're writing bid specs because there can be such a variation in performance between processors that are running at the same clock speed."

-- Todd Swank, Vice President of Marketing, Nor-Tech

"Better news [than breaking the 4GHz barrier] would be the ability to throw in killer graphics, processing power and unlimited battery life in a processor that's the size of my fingernail. Of course that's not realistic yet, but we're getting there."

-- Rahul Sood, Chief Technology Officer, Global Voodoo Business Unit, Hewlett-Packard

"Absolute clock speeds is old-world thinking, to steal a phrase. With multiple threads, Turbo Boost, on-chip overclocking, etcetera, the pure clock speed measurement is no longer the determining factor. Further, and many people forget this, with the increase in chip complexity, especially with multi-cores, specialized functions and multi-threading, the way software is designed and compiled can be far more important to the speed at which a program runs than just measuring the pure CPU speed."

-- Jack Gold, Analyst, J. Gold Associates