64-Bit Processors and Products

Windows will support two 64-bit processor architectures. Support for 64-bit processors benefits memory-intensive applications, such as on-line analytic processing (OLAP) systems, and compute-intensive workstation applications (e.g., computer-aided design). However, to gain the full benefits, companies also need to be running 64-bit versions of their applications.

Processor architectures to be supported in Windows include the following:

x86-64. This architecture was introduced in the AMD64 Athlon and Opteron 64-bit processor families and has been adopted by Intel for its Extended Memory 64 (EM64T) processors. The x86-64 architecture is designed to support large memories and compute-intensive 64-bit applications, while also performing acceptably on 32-bit code and on “just-in-time” compiled code such as that used in .NET Framework applications. No Microsoft products support x86-64 today. However, x86-64 will be supported in 64-bit “extended” editions of Windows due for production release in 2005. The next major versions of some server products, including SQL Server, Exchange, and BizTalk Server, will also support x86-64.