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BIOS Setup
DRAM Frequency Set (Mhz)
This field is used to set a memory clock limit on the system. This will
prevent the memory speed from running faster than this frequency.
Command Per Clock (CPC)
This field is used to enable the DRAM commands and address that
will be driven for 2 clock cycles and select the second phase of the
2 clock command and address.
CAS Latency Control (Tcl)
This field is used to select the clock cycle of the CAS latency time.
The option selected specifies the timing delay before SDRAM starts
a read command after receiving it.
RAS# to CAS# Delay (Trcd)
When DRAM refreshes, both rows and columns are addressed
separately. This field is used to select the delay time from RAS (Row
Address Strobe) to CAS (Column Address Strobe) when reading
and writing to the same bank. The lesser the clock cycle, the faster
the DRAM’s performance.
Min RAS# Active Time (Tras)
This field is used to select the minimum time RAS takes to read
from and write to a memory cell.
Row Precharge Time (Trp)
This field is used to select the number of cycles that is allowed for
Row Address Strobe (RAS) to precharge. If insufficient time is
allowed for the RAS to accumulate its charge before DRAM
refreshes, refreshing may be incomplete and DRAM may fail to retain
data.
Row Cycle Time (Trc)
This field is used to select the row cycle time, RAS# active or auto
refresh of the same bank.
