Differences Between Windows Server 2003 Standard Edition and Enterprise Edition.
The Standard Edition of Windows Server 2003 supports up to 4 GB of RAM and four-way SMP.
The Enterprise Edition of Windows Server 2003 supports eight processors and 32 GB of RAM, also eight-node clustering including SAN and geographically dispersed clustering.
Other features that distinguish the Enterprise Edition from the Standard Edition: Support for Microsoft Metadirectory Services (MMS), which enables the integration of multiple directories, databases, and files with Active Directory. Hot Add Memory, so that you can add memory to supported hardware systems without downtime or reboot. Windows System Resource Manager (WSRM), which supports the allocation of CPU and memory resources on a per-application basis.