User`s guide

Processor Board Features
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The first four module group installs in memory bank A, the second in bank B, the third
in bank C and the last in Bank D.
System memory begins at address 0 and is continuous (flat addressing) up to the
maximum amount of DRAM installed (exception: system memory is noncontiguous in
the ranges definedas memoryholes using configurationregisters).The system supports
both base (conventional) and extended memory.
• Base memory is located at addresses 00000h to 9FFFFh (the first 1 MB).
• Extended memory begins at address 0100000h (1 MB) and extends to FFFFFFFFh (4
GB), which is the limit of supported addressable memory. The top of physical
memory is a maximum of 4 GB (to FFFFFFFFh).
Note: Addressable memory can be extended to 64 GB under certain configurations, but
this server is configured to support 4 GB.
Some operating systems and application programs use base memory while others use
both conventional and extended memory. Examples:
• Base memory: Windows NT and LINUX
• Conventional and extended memory: Windows NT and LINUX
MS-DOS does not use extended memory; however, some MS-DOS utility programs like
RAM disks, disk caches, print spoolers, and windowing environments use extended
memory for better performance.
BIOS automatically detects, sizes, and initializes the memory array, depending on the
type, size, and speed ofthe installedDIMMs, andreportsmemory sizeand allocationto
the system via configuration registers.
Ina4GBconfiguration, a small part ofmemory(typically 32 MB) is notremappedabove
4GB.Ifyouroperatingsystemdoesnotsupportmorethan4GBofphysicalmemory,this
small part of the memory is effectively lost.