Copernicus, Newton, Kepler, and Einstein all developed “laws” or theorems so fundamental to our understanding of the universe that they are known to every schoolchild. Moore’s Law isn’t quite up there with E=mc2 on the greatest-hits list, but it isn’t far behind. The notion that computing power would double about every 18 months as engineers figure out how to build ever-faster microprocessors has held up amazingly well.

Many of those advances, however, have been made within the confines of the “conventional” (if one dares apply such a word to microchips) 32-bit architecture. But since the mid-’90s, some computers have enjoyed greatly expanded memory and processing speeds, thanks to a 64-bit architecture. They’ve tended to be expensive, proprietary, and complex computers used mainly by scientists and engineers. Now relatively inexpensive 64-bit processors bring this speed advantage to the everyday computers that power Websites, corporate applications, and even your home PC.

Sixty-four-bit computing represents the third major architecture shift since the invention of the microprocessor. The first shift, in the early 1980s, brought processors from 8-bit to 16-bit computing. The second came in the late ’80s through the early ’90s with the move from 16-bit to 32-bit computing. The third shift appeared in the mid-’90s, when the first proprietary 64-bit processors appeared. More recently, Intel, Advanced Micro Devices, and Apple Computer have introduced 64-bit processors for desktop computers and servers running the Windows, Linux, and Mac operating systems.

How It Works

The term 64-bit refers to the size of the addresses the processor uses to organize the system’s main memory banks. Sixty-four-bit systems must use wider registers so that the programs running on the computer can calculate these larger addresses. But for reasons we won’t go into here, the expansion of the main memory address range works wonders on the overall ability of the chip to crunch data. A 32-bit processor can directly address as many as 4 gigabytes (billion bytes) in the main memory. By contrast, a 64-bit system can address as many as 16 exabytes—that’s 16 billion gigabytes.

That may sound like nerdy nattering, but computers with 64-bit processors can run database and other business programs faster, manage larger data files and databases, allow more concurrent users and applications to access data, and reduce software-licensing fees. Basically, the more memory a processor can access at a time, the less it relies on information stored on the computer’s disk drive. By analogy, consider how quickly you can call a friend whose telephone number you’ve memorized; now consider the time needed to call someone whose number you have to look up.

“The less I have to go to disk, the faster my applications run,” explains Jeff Jones, director of strategy for IBM DB2 information-management software. “The faster my applications run, the quicker I can make business decisions.”

As memory costs have dropped (10 years ago, 4 gigabytes of memory cost about $100,000; today the same 4 gigs go for under $2,000), the processor has become more of a bottleneck. The notion of a chip that can tackle 16 exabytes may seem like too much of a good thing, but companies are already figuring out ways to optimize their older applications to take advantage. New applications written expressly for 64-bit architectures are being developed by Microsoft and others.

Why You Should Care

The main advantages of 64-bit are faster computing and lower IT costs.

The two work hand in hand. The speed advantage, explained above, means complex applications formerly requiring computers costing $25,000 and up can now be run on computers costing as little as $2,000.

Databases, an application used by nearly every business, should get an especially huge boost. When a database accesses records on a drive, it leaves a copy of that material in the system’s main memory to quicken subsequent uses of that data. “If the database needs it again, it only takes a few hundred microseconds to pull it from main memory, instead of tens of milliseconds from disk,” explains Insight 64’s Nathan Brookwood, principal analyst at the market-research firm. A few million microseconds here, a few million there, and you’re talking real time saved.

Also, software-license fees could drop with wider use of 64-bit computing. Although licensing schemes are in flux, many enterprise-software vendors charge license fees by the processor. Given the same application, fewer 64-bit processors are needed; hence, lower licensing fees.

What 2004 Will Bring

The market for 64-bit systems is worth an impressive $30 billion, says Brookwood, in part because microprocessor makers haven’t let the economic downturn slow their progress. In fact, last year Intel and AMD collectively spent nearly $5 billion on R&D, and one result has been a wave of attractive new chips—and computers built around them.

Still, 64-bit computing for the masses faces a classic chicken-and-egg situation: faster processors don’t mean much to IT managers unless there’s computer hardware and software to take advantage of them. But hardware and software vendors aren’t inclined to build 64-bit-ready products until IT managers start buying them.

The stalemate may end soon. In the coming year, more vendors are expected to introduce computers and software optimized for 64-bit chips, and more IT managers will undoubtedly buy these products. Already Dell, Microsoft, SAP, and Oracle have discussed future products, many of which will ship next year.

Apple’s in the Eye of the 64-Bit Storm

Earlier this year, Intel added a new model to its Itanium line of 64-bit processors, just after a new Itanium-ready version of Windows XP from Microsoft debuted, prompting hardware vendors such as Dell and HP to build computers around the new chips. Intel says most desktop machines will do just fine with 32-bit chips, but competitor AMD launched its Athlon 64-bit processor at the end of September and said the time is now for 64-bit computing to go mainstream. Apple Computer agrees, and has been touting the processing muscle of its new power Mac G5. “Our customers crave performance,” says Tom Boger, Apple’s Power Mac worldwide marketing director.

Indeed, Apple landed a whopping 100,000 orders between June, when the machine was announced, and the first day of shipments in August. That kind of demand has encouraged important third-party developers—including Adobe, with its popular Photoshop Software—to update their programs, a sign of things to come for Windows PCs.