When you install Microsoft Windows 2000 Professional on an older portable computer that does not have a battery, and then enable Advanced Power Management (APM) on the computer, there is no Standby
option in the Shut Down Windows
This behavior occurs because although Windows 2000 primarily supports the Advanced Configuration and Power Interface (ACPI) standard, it also includes APM to support upgrading of older, non-batteried portable computers to Windows 2000. Such computers can benefit from the APM 'power-off' feature. Newer portable computers support ACPI, which provides full power management functionality.
This behavior is by design.