Redmond (WA) - UPDATE - Microsoft will release the second release candidate of the 64-bit version of Windows XP Professional as a free download on Friday. The company will also offer downloads of Windows XP Professional x64 RC2 and Windows Server 2003 SP1 RC2.

All three downloads will be available starting at 6:00 pm PST today, but only the Windows XP Professional x64 Edition RC2 code will be available to users in the framework of Microsoft’s Customer Preview Program, according to an email from the company. The release candidates for Windows Server 2003 SP1 and Windows Server 2003 x64 will be limited to participants of the technical beta program.

According to a statement release by Microsoft on Tuesday, users "can expect considerable performance improvements across a variety of workloads" when moving from 32-bit Windows to 64-bit. The company said that it will begin accepting hardware device submissions for both Windows XP Professional x64 Edition and Windows Server 2003 x64 Editions for the "Designed for Windows" logo program in the coming weeks. Both operating systems are scheduled to be available "in the first half of 2005".

Windows XP Professional x64 RC2 will be a 450 MByte download and is supported by AMD’s Athlon 64 and Opteron processors as well as Intel’s Xeon and Pentium 4 processors with EM64T extension. Itanium-based systems are not supported. System requirements call for 256 MByte memory, 1.5 GByte harddrive space. The RC2 is a time-limited version of the operating system and will run for 360 days, Microsoft said.

The RC2 update for Windows Server 2003 SP1 includes security, reliability and performance enhancements, and will also be available in the first half of 2005. Windows Server 2003 SP1 also serves as the underlying technology for the x64 releases and Windows Server 2003 R2.

Editor’s note : Microsoft informed THG on Thursday that the site of the Customer Preview Program experienced a ’hiccup’ which caused a delay of the availability of the Windows XP Professional x64 Edition RC2 download. The company now expects to make the download available sometime on Friday, February 11.