Aaeon PCM-6896, Руководство пользователя

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58 PCM-6896 User Manual
SDRAM RAS-to-CAS Delay
This field lets you insert a timing delay between the CAS and RAS strobe
signals, used when DRAM is written to, read from, or refreshed. Fast
gives faster performance; slow gives more stable performance. This field
applies only when synchronous DRAM is installed in the system.
SDRAM RAS Precharge Time
If an insufficient number of cycles is allowed for the RAS to accumulate its
charge before DRAM refresh, the refresh may be incomplete and the
DRAM may fail to retain date. Fast gives faster performance; slow gives
more stable performance. This field applies only when synchronous
DRAM is installed in the system.
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.
Video BIOS Cacheable
Selecting Enabled allows caching of the video BIOS ROM at C0000h to
C7FFFh, resulting in better video performance. However, if any program
writes to this memory area, a system error may result.
Memory Hole At 15-16m
In order to improve performance, certain space in memory is reserved for
ISA cards. This memory must be mapped into the memory.
CPU Latency Timer
During enable, a deferrable CPU cycle will only be Deferred after it has
been in Snoop Stall for 31 clocks and another ADS# has arrived. During
disable, a deferrable CPU cycle will be deferred immediately after the
GMCH recieves 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.