User's Manual
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C. SDRAM Cycle Length
When synchronous DRAM is installed, the number of the clock cycles of CAS
latency depends on the DRAM timing. Do not reset this setting from the default
value specified by the system designer.
D. Memory Hole at 15M-16M
Enabling this function will reserve the memory address space between 15MB and
16MB for ISA expansion cards. However, enabling this function will result in
not allowing the system to have access to memory above 16MB. Please note
that some expansion cards require this setting to be enabled. The default setting
is Disabled. If Auto Configuration is enabled, you must set the DRAM timing
function to 60ns or 70ns, depending on the type of DRAM you install.
E. System BIOS Cacheable
Enabling this function 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. Caching the system BIOS results in better
performance than shadowing the system BIOS as discussed in Section 3-2.
F. Video RAM Cacheable
Enabling this function will allows caching of the video RAM, resulting in
better system performance. However, if any programs write to this memory
area, a system error may occur.
G. AGP Aperture Size
This function determines the amount of system memory that is given to the AGP
card. Options range from 4MB to 128MB. This is a dynamic memory allotment
in that the AGP card will only use the amount of memory that it needs. The
remaining memory not in use will be available for the system to use. For example,
if 16MB is allotted to the AGP card and the card only needs 8MB, the remaining
8MB will be available for system use.
H. Flash BIOS Protection
The mainboard manufacturer developed BIOS protection technology that protects
the System BIOS from accidental corruption by unauthorized users or computer
viruses. When enabled, the BIOS data cannot be changed when attempting to
update BIOS with the FLASH utility. When disabled, the BIOS data can be updated
by using the FLASH utility.
