Description of Windows Server 2003 support and of Windows 2000 support for multiple-CPU computers with mixed Stepping levels

This article discusses Microsoft Windows Server 2003 support and Microsoft Windows 2000 support for computers with multiple central processing units (CPUs) with mixed Stepping levels.

Computers with multiple CPUs that have mixed Stepping levels use the features of the least capable CPU. For example, if the first CPU supports features A, B, and C, and the second CPU supports feature A, only feature A is used on both CPUs. Also, for these two CPUs to work together, features B and C may need to be disabled on the first CPU.

Note Windows Server 2003 and Windows 2000 log Stepping-level mismatch occurrences as informational events in the system event log.

To view CPU Stepping levels on your computer, follow these steps:

1. Click Start, point to Programs, point to Administrative Tools, and then click Computer Management.
2. Double-click the System Information folder, and then click the System Summary folder.

Check the Processor line to view the CPU Stepping levels.

According to Intel, certain Intel CPUs with mixed Stepping levels can be used together if the Basic Input/Output System (BIOS) supports both Stepping levels. Intel does not prevent CPUs with mixed Stepping levels from working together. However, Intel recommends that you contact the motherboard vendor for more information about using CPUs with mixed Stepping levels. All possible combinations of hardware and CPU Stepping levels have not been tested. Microsoft provides third-party contact information to help you find technical support. This contact information may change without notice. Microsoft does not guarantee the accuracy of this third-party contact information.

For more information about using CPUs with mixed Stepping levels, contact your motherboard manufacturer.