CHAINTECH 6BDU0, Руководство пользователя

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User's Manual
30
B. DRAM Data Integrity Mode
BIOS automatically detects the presence of ECC DIMMs (72-bit modules). However,
to take advantage of ECC you must set this function at "ECC." If any non-parity
DIMMs are installed, the memory operates in non-parity mode only and this
function must be set at "Non-ECC."
C. 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.
D. Video BIOS Cacheable
Enabling this function allows caching of the video BIOS ROM at C0000h-C7FFFh,
resulting in better video performance. However, if any program writes to this
memory area, a system error may result. Caching the video BIOS results in better
performance than shadowing the video BIOS as discussed in Section 3-2.
E. 8-bit I/O Recovery Time & 16-bit I/O Recovery Time
Back-to-back CPU or PCI master originated 8-bit and 16-bit cycles have an arbitrary
delay of at least 3.5 system clock cycles. This category is used to add additional
recovery delay between 8-bit and between 16-bit cycles. This delay takes place
because the PCI bus is much faster than the ISA bus. The options are 1 to 8
and N/A.
F. 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.
G. AGP Aperture Size (MB)
This function determines the amount of system memory that is given to the AGP
card. Options range from 4MB to 256MB. 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 are alloted to the AGP card and the card only needs 8MB, the remaining
8MB will be available for system use.