08.228.2005 - Not all processors on some multiprocessor computers are recognized by x64-based versions of Windows Server 2003 (KB899656)

On some multi-processor x64 systems, Windows Server 2003 SP1 does not correctly recognize all configured processors when hyper-threading is enabled. This occurs when the BIOS has been designed to reprogram the APIC (advanced programmable interrupt controllers) ID’s at boot time. Most x64 systems are not affected. Do not install this update unless you are experiencing the stated problem. - Download Microsoft Windows Server 2003 (x64) - View Microsoft Knowledge Base Article - 899656 - Visit Microsoft Corporation