Microsoft late Tuesday came one step closer to releasing the 64-bit editions of Windows XP and Windows Server 2003 by posting the new Release Candidate 2 (RC2) versions to its beta test site.

The Redmond, Wash.-based developer also released RC2 for Windows Server 2003 Service Pack 1 (SP1) on Tuesday. All three products are on track, said a Microsoft spokeswoman, for release in the first half of 2005. Some analysts have targeted April; Microsoft will hold its Windows Hardware Engineering Conference (WinHEC) in Seattle April 25 through 27.

Windows Server 2003 SP1, which has been characterized as the server side to Windows XP SP2, stresses security and like XP SP2, is less an update than a revised OS with several new features. A new Security Configuration Wizard in SP1, for instance, will walk administrators through the process of reducing a server's attack profile by setting options to block unnecessary ports, change registry keys, and configure audit settings.

More information on RC2, and links to its download, can be found on the Microsoft site here.

The newest code for Windows Server 2003 x64 Editions and Windows XP Professional x64 Editions will be made available to members of the Microsoft technical beta program, although RC2 for XP Pro x64 can also be downloaded through the Customer Preview Program.

Both these operating systems are meant to ease the transition to 64-bit computing, since they run both 32- and 64-bit applications. "With the availability of the latest hardware advancements, customers can expect considerable performance improvements across a variety of workloads in [these editions] compared to the 32-bit versions of these products," the spokeswoman said.

Also on Tuesday night, Microsoft began accepting hardware device submissions for the 64-bit versions of both Windows XP and Windows Server 2003 for the "Designed for Windows" logo program, the spokeswoman said.