Most of today's high-volume server processors manipulate data and instructions in 32-bit chunks. A 64-bit processor can handle chunks that are twice as big. This doubles the potential throughput per operation and provides two key benefits:

• Address large amounts of physical memory. This allows an application to store vast amounts of data in the main memory.
• Manipulate high-precision data more quickly, since it can process more bits in each operation.

The Intel^® Extended Memory 64 Technology (EM64T) is an enhancement to Intel's IA-32 architecture. The main idea of EM64T is to give the Intel^® Xeon^® and Pentium^® processors access to greater amounts of memory than 4 Gigabytes. 4 GB is the standard memory size limit of 32-bit processors. With 64-bit memory address limits, the theoretical memory size limit would be 16 Billion Gigabytes (16 Exabytes). To utilize this feature on the servers, a 64-bit capable OS and OS specific drivers are needed. There is no BIOS setup option to enable or disable this support.