IBM CI5VGM Series, User Manual

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Chapter 3 BIOS Configuration
52 CI5VGM User’s Manual
Video BIOS Cacheable
When enabled, access to video BIOS addressed at C0000H to C7FFFH is
cached, provided that the cache controller is disabled.
System BIOS Cacheable
When enabled, access to the system BIOS ROM addressed at
F0000H-FFFFFH is cached, provided that the cache controller is
disabled.
Memory Hole at 15MB - 16MB
In order to improve performance, certain space in memory can be
reserved for ISA cards. This field allows you to reserve 15MB to 16MB
memory address space to ISA expansion cards. This makes memory from
15MB and up unavailable to the system. Expansion cards can only access
memory up to 16MB. By default, this field is set to
Disabled .
AGP Aperture Size (MB)
The field sets aperture size of the graphics. The aperture is a portion of
the PCI memory address range dedicated for graphics memory address
space. Host cycles that hit the aperture range are forwarded to the AGP
without any translation. The options available are 4M, 8M, 16M, 32M,
64M, 128M and 256M. The default setting is
64M .
Cyrix M2 ADS# delay
This field is only visible when your system supports a Cyrix M2
processor. It enables or disables the ADS# delay signal for Cyrix M2.
Auto Detect DIMM/PCI Clk
When enabled, the system automatically shuts off clocks of unused
DIMM/PCI slots. The default setting is
Disabled . This field is for CE
testing use only.
Spread Spectrum
This field sets the value of the spread spectrum. Options are Disabled,
1.8% (CNTR), 0.6% (CNTR), 1.8% (DOWN), and 0.6% (DOWN). The
default setting is 0.6% (DOWN). The default setting is
Disabled . This
field is for CE testing use only
.
OnChip USB
This filed allows you to enable or disable the USB function. The default
setting is
Enabled .