Intel released its 64-bit Xeon processor this week, finally joining the 64-bit market dominated by AMD's Athlon 64 and Opteron.

Intel's first x64 chips, a set of new Xeon chips, are compatible with AMD's 64 bit chips, including the Athlon 64 and Opteron. And servers based on any x64 chip mix and match 32-bit and 64-bit operating systems and applications, all of which run at full speed.

"Availability of Intel's new server platforms with Extended Memory 64 Technology [EM64T] marks an exciting milestone that will accelerate customer adoption of 64-bit computing," said Bob Muglia, the senior vice president of Microsoft's Windows Server Group. "The performance and scalability benefits of 64-bit Windows Server 2003 and SQL Server 2005 on Intel Xeon processor-based systems enable Microsoft and Intel to deliver the benefits of 64-bit technology while providing customers investment protection and an easy migration path from today's 32-bit applications."

The new Intel Xeon processors feature Intel's EM64T technology, which lets the chips address far more memory than the 4 GB limit required by 32-bit designs. Intel has also added unique features to its own designs in a bid to differentiate them from AMD's. For example, the new Xeon processors include Demand Based Switching with Enhanced Intel SpeedStep Technology to dynamically adjust the processor's power usage.

The chips are also accompanied by the new Intel E7520 and E7230 chipsets, which support high-end memory and PCI Express. The new Xeon currently tops out at 3.6 GHz, though versions are available starting at 2.8 GHz, Intel says. On Monday, a number of PC makers, including Dell, HP, and IBM, unleashed server systems featuring the new processor and chipsets.

Native 64 bit software is still trying to catch up. Microsoft is currently beta testing an x64 version of Windows Server 2003, the final version of that product won't ship until early 2005 at the earliest. Today, customers who purchased x64-based servers will receive the currently available 32-bit version of Windows Server instead.