Compaq Deskpro AP550 - Page 163

Physical and Operating Specifications
7-7
Table 7-5
System Memory Map
Memory Address Size System Function
FFFFFFFFh to FFF80000h 512 KB System ROM
FEEFFFFFh to FEE00000h 1024 KB Local APIC address range
FECFFFFFh to FEC00000h 1024 KB I/O APIC address range
FEBFFFFFh to TOM (Top of
Memory)
Depends on memory installed PCI memory expansion board
TOM (Top of Memory) – 1 to
TOM – 64 KB
64 KB (However, USB buffer not
applicable to all system
configurations.)
USB memory buffers
TOM (Top of Memory) – 64 KB –
1 to 01000000h
Depends on memory installed HOST memory expansion
00FFFFFFh to 00100000h 15,360 KB HOST memory expansion
000FFFFFh to 000F0000h 64 KB System ROM
000EFFFFh to 000E0000h 64 KB Expansion system ROM
000DFFFFh to 000C0000h 128 KB Option ROM
000BFFFFh to 000A0000h 128 KB Video RAM
0009FFFFh to 00000000h 640 KB Base memory
1 KB = 1024 bytes. Any memory above host memory is non-cacheable.