At WinHEC 2005, Microsoft announced it is finally ready to bring 64-bit computing to the mainstream and is shipping x64 editions of Windows XP and Windows Server 2003. The 64-bit versions of Windows were released to manufacturing in late March and will now be available from PC vendors.

Microsoft has big plans for 64-bit computing, but moving towards the next-generation architecture won't be an easy transition. The new x64 Windows releases will not be sold on retail shelves - only as an option from manufacturers selling PCs with 64-bit processors from AMD and soon Intel.

Because most software is not designed for 64-bit computers, x64 editions of Windows also run 32-bit applications. Such a feature is almost a requirement of the operating system, as Microsoft's own 64-bit capable programming environment, Visual Studio 2005, is still in beta.

Other development software makers, such as Borland, have publicly said they are in no rush to support 64-bit systems, citing the costs to target such a small market. Nonetheless, Microsoft has said it expects 64-bit machines to make up a significant number of PCs that ship next year.

"We believe this industry move will be the easiest to date, because the 64-bit versions of Windows we've developed allow customers to run 32-bit as well as 64-bit applications," said Microsoft Group VP Jim Allchin. "It's a best-of-both-worlds model that lets customers integrate new and more powerful technologies at their own pace without having to risk their current technology investments or abandon their existing systems and applications."

Jupiter Research senior analyst Joe Wilcox, however, questions whether Microsoft will see the uptake it hopes.

"Microsoft may make big noise about 64-bit Windows, but I don't see it as much of a big deal on the desktop. For most people, for most of what they do, 32-bit delivers plenty of performance," Wilcox told BetaNews. "My bet: the 64-bit user benefit will be missing for most people. Even if all PC manufacturers starting selling only 64-bit systems tomorrow, I foresee modest 64-bit Windows adoption on the desktop."

Although Microsoft is shipping over 16,000 drivers with the 64-bit Windows editions, hardware support will still be a major hurdle.

Redmond is planning to use WinHEC to push manufacturers into making drivers for the new platform. Microsoft also plans to soon begin accepting applications for Windows XP x64 Edition in its "Designed for Windows" logo program.

"There isn't enough supporting infrastructure," says Jupiter's Wilcox. "Microsoft made the move from 16-bit to 32-bit with a new operating system, new version of Office and reasonable hardware driver support. Right now there is a vacuum of applications and supporting hardware. Big 64-bit talk may be good marketing, but talking the talk isn't the same as customers walking the walk."