Windows Server 2003 for 64-Bit Extended Systems
Windows Server 2003 for 64-Bit Extended Systems provides high performance for both 32-bit and 64-bit applications on the same system. The underlying architecture is based on 64-bit extensions to the industry-standard x86 instruction set, allowing today's 32-bit applications to run natively on 64-bit extended processors such as AMD Opteron. At the same time, new 64-bit applications are executed in 64-bit mode, which processes more data per clock cycle, allows greater access to memory, and speeds numeric calculations. Read the newly published information here.