Intel® 82854 Graphics Memory Controller Hub (GMCH)

Figure 6. Detailed View of System Address Map

PCI Memory

Range

Optional ISA

Hole

DOS

Compatibility

Memory

4 GB max

TOM

 

0FFFFFh

 

 

 

SBIOS

 

1 MB

 

 

 

 

 

 

Upper

 

 

 

 

 

 

 

 

BIOS Area

 

 

 

 

0F0000h

 

 

 

 

 

 

 

 

 

 

(64 kB)

 

 

 

 

 

 

 

 

Extended

 

960 kB

 

 

0EFFFFh

 

 

 

 

 

 

SBIOS Lower

 

 

 

 

0E0000h

 

 

 

BIOS Area ( 64

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1 GB

 

0DFFFFh

 

 

kB) 16 kB x 4

 

 

 

 

 

 

 

 

Card

 

896 kB

 

 

 

 

 

 

 

 

16 MB

 

 

 

 

 

BIOS and

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Buffer Area

 

 

 

 

 

 

 

 

(128 kB)

 

 

15 MB

 

 

 

 

 

16 kBx8

 

 

 

 

 

 

 

 

 

 

 

 

0C0000h

 

 

 

 

 

 

0BFFFFh

 

 

 

 

 

 

Standard

 

 

 

 

 

 

 

 

 

768 kB

 

 

 

 

 

 

PCI/ISA

 

 

 

 

DOS

 

Video

 

 

 

Compatibility

 

Memory

 

 

1 MB

 

(SMM

 

 

 

Memory

 

 

 

 

 

 

Memory)

 

 

 

 

 

 

 

 

128 kB

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

640 kB

 

 

0A0000h

 

 

640 kB

 

09FFFFh

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

DOS Area

0 B

000000h

5.2DOS Compatibility Area

This compatibility region is divided into the following address regions:

0 - 640 kB DOS Area

640 - 768 kB Video Buffer Area

768 - 896 kB in 16-kB sections (total of eight sections) - expansion area

896 -960 kB in 16-kB sections (total of four sections) - extended system BIOS area

960 kB - 1 MB system BIOS area

There are 16 system memory segments in the compatibility area. Thirteen of the system memory ranges can be enabled or disabled independently for both Read and Write cycles.

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D15343-003

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Image 112
Intel D15343-003 manual DOS Compatibility Area, Detailed View of System Address Map