Appendix B. System Address Maps; System Memory Map - IBM NetVista X40 Technical Information Manual

Appendix B. System address maps

System memory map

Table 32. System memory map
Address range
(decimal)
0–512 KB
512–639 KB
639–640 KB
640–767 KB
768–800 KB
800–896 KB
896 KB–1 MB
1–16 MB
16–4096 MB
4096–4120 MB
© Copyright IBM Corp. 2000
The first 640 KB of system board RAM is mapped starting at address hex 0000000. A
256 byte area and a 1 KB area of this RAM are reserved for BIOS data areas. Memory
can be mapped differently if POST detects an error.
Address range (hex)
00000–7FFFF
80000–9FBFF
9FC00–9FFFF
A0000–BFFFF
C0000–C7FFFF
C8000–DFFFF
E0000–FFFFF
100000–FFFFFF
1000000–FFDFFFF
FFFE0000–FFFFFFFF
Size Description
512 KB Conventional
127 KB Extended conventional
1 KB Extended BIOS data
128 KB Dynamic video memory display
cache
32 KB Video ROM BIOS (shadowed)
96 KB PCI space, available to adapter
ROMs
128 KB System ROM BIOS (main memory
shadowed)
15 MB PCI space
4080 MB PCI space (positive decode)
128 KB System ROM BIOS
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