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Please refer to section 3-6-1
System BIOS Cacheable
Selecting Enabled allows caching of the system BIOS ROM at F0000h-FFFFFh, resulting in
better system performance. However, if any program writes to this memory area, a system
error may result. The settings are: Enabled and Disabled.
Video BIOS Cacheable
Select Enabled allows caching of the video BIOS, resulting in better system performance.
However, if any program writes to this memory area, a system error may result. The settings
are: Enabled and Disabled.
Memory Hole At 15M-16M
You can reserve this area of system memory for ISA adapter ROM. When this area is
reserved, it cannot be cached. The user information of peripherals that need to use this area of
system memory usually discusses their memory requirements. The settings are: Enabled and
Disabled.
CPU Latency Timer
During Enabled, A deferrable CPU cycle will only be Deferred after it has been in a Snoop
Stall for 31 clocks and another ADS# has arrived. During Disabled, A deferrable CPU cycle
will be Deferred immediately after the GMCH receives another ADS#.
Delayed Transaction
The chipset has an embedded 32-bit posted write buffer to support delay transactions cycles.
Select Enabled to support compliance with PCI specification version 2.1. The settings are:
Enabled and Disabled.
On-Chip Video Window Size
This option enabled/disabled the on-chip video windows size for VGA driver use. The
settings are: enabled, Disabled.
AGP Graphics Aperture Size
This option determines the effective size of the graphics aperture used in the particular PAC
configuration. The AGP aperture is memory-mapped, while graphics data structure can reside
in a graphics aperture. The aperture range should be programmed as not cacheable in the
processor cache, accesses with the aperture range are forwarded to the main memory, then
PAC will translate the original issued address via a translation table that is maintained on the
main memory. The option allows the selection of an aperture size of 32MB, 64MB.
3-6-1 SDRAM Timing Setting