Contec SPC-8450-LVA, Руководство пользователя

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7. BIOS Setup
48
SPC-8450-LVA
Description Choice
RAM Timing Selectable
The value in this field depends on performance parameters
of the installed memory chips (DRAM). Do not change the
value from the factory setting unless you install new memory
that has a different performance rating than the original
DRAM
CAS Latency Time
When synchronous DRAM is installed, the number of clock
cycles of CAS latency depends on the DRAM timing. Do not
reset this field from the default value specified by the system
designer.
You can select CAS latency time in HCLK of 2/2 or 3/3. The
system board designer should set the values in this field,
depends on the DRAM installed specifications of the
installed DRAM or the installed CPU.
Active to Precharge delay
Select the precharge delay timer.
DRAM 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; and Slow
gives more stable performance. This field applies only when
synchronous DRAM is installed in the system.
DRAM RAS# Precharge
The precharge time is the number of cycles it takes for the
RAS to accumulate its charge before DRAM refresh. If
insufficient time is allowed, refresh may be incomplete and
the DRAM may fail to retain data.