Digital Equipment FR-902AA-A3, Service Maintenance Manual

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Digital STARION 400i - 900i PC Utilities & Configuration
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Memory and Cache
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Menu Fields Settings Comments
System BIOS
shadow Not user
selectable,
permanently set
to Enabled The main logic board reserves an area of DRAM, called "shadow
memory" for a copy of system BIOS ROM. This DRAM is write-
protected and has the same addresses as the system BIOS ROM
locations. When system BIOS ROM is shadowed, the ROM
information is copied into an appropriate area in DRAM. This
increases the computer's performance because the system BIOS
instructions are in fast DRAM instead of ROM.
Cache system
BIOS Enabled
Disabled This option enables the system BIOS to be cached in the internal
cache and external cache (if installed). This increases computer
performance because BIOS instructions can be executed in cache
instead of RAM.
Video BIOS
shadow Enabled
Disabled The main logic board reserves an area of DRAM, called "shadow
Memory", for a copy of video BIOS ROM. This DRAM is write-
protected and has the same addresses as the video BIOS ROM
locations. When video BIOS ROM is shadowed, the ROM
information is copied into an appropriate area in DRAM. This
increases the computer's performance because the video BIOS
instructions are in fast DRAM instead of ROM. For PCI VGA cards,
video BIOS is always shadowed, regardless of this field’s setting.
Cache video
BIOS
Enabled
Disabled This option enables the video BIOS to be cached in the internal cache
and external cache (if installed). This increases computer
performance because video BIOS instructions can be executed in
cache instead of RAM.
Shadow 16K
at:
C8000h
CC000h
D0000h
D4000h
D8000h
DC000h
Enabled
Disabled Enables or disables shadowing of individual segments of ROM to
increase computer performance.
AT bus space Disabled Memory hole not available; upper memory is contiguous.
F80000h,
0.5 MB Sets the memory hole at address F80000 with 0.5 MB memory
available.
F00000h, 1
MB Sets the memory hole at address F00000 with 1 MB memory
available.
Extended
memory
report
Compatibility
Non-
compatibility
Selects the BIOS report mechanism for memory amount.
Select Compatibility when using a conventional operating system.
Select Non-compatibility for extended memory above 64 MB under
Windows NT v3.1.