After you upgrade Windows Server 2003 to SP1 (Service Pack 1), the Server Balanced Processor Power and Performance power scheme is NOT available in Control Panel / Power Options. The Minimal Power Management is available.

The Server Balanced Processor Power and Performance power scheme is only available if you install from a slipstream version of Windows Server 2003 SP1.

To workaround this behavior, use the Minimal Power Management power scheme, which provides the same functionality, including support for the adaptive processor throttling policy used by some processors.