Memory Map

Table 31 lists the system memory map. When BIOS allocates memory space to PCI devices, it starts just below the APICs and continues downward. Assigning memory space to PCI devices does not decrease the total available memory in the system because this memory is “reclaimed” above 4 GB.

The server does not support memory gaps from 512 KB to 640 KB and from 15 MB to 16 MB. These regions are treated as normal system memory.

Table 31. Memory Map

Address Range

00000000 – 0009FFFF

000A0000 – 000AFFFF

000C0000 – 000D7FFF

000C0000 – 000D7FFF

000D8000 – 000DBFFF

000DC000 – 000DFFFF

000E0000 – 000FFFFF

00100000 – PCI Memory allocated to first PCI device

FEC00000 – FEC0FFFF

FEC10000 – FEC1FFFF

FEC20000 – FECFFFFF

FEE00000 – FEF00000

FF000000 – FFDFFFFF

FFE00000 – FFFFFFFF

100000000 – 1FFFFFFFF

Amount

640K

128K

96K

96K

16K

16K

128K

64K

64K

896K

1MB

14MB

2MB

4GB

Function

Base (conventional) System Memory

ISA Video buffer

Add-in Options ROM’s (Video, SCSI…)

Add-in Options ROM’s

Allocated to Run time user binary if enabled/programmed, otherwise can be used for options ROM’s

Allocated to Console Redirection if enabled, otherwise can be used for options ROM’s

System BIOS Shadowed

Typically it can go up to 3GB

Reserved. Unused on this platform

Reclaimed. If main memory exceeds this region

IOAPIC allocated to the PID

Reclaimed. If main memory exceeds this region

Reserved

Reclaimed. If main memory exceeds this region

LOCAL APIC

Reclaimed. If main memory exceeds this region

Unused. Reclaimed. If main memory exceeds this region

Main System BIOS

If memory exists

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Technical Reference

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Intel SRPL8 manual Memory Map, Address Range, Amount, Function