Acer Aspire SA85, Service Manual

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34 Chapter 2
DRAM Clock/Timing Control
Parameter Description
Current CPU Frequency Detect the current CPU Frequency
Current DRAM Frequency Detect the current DRAM Frequency
DRAM Timing Control Enables you to select the CAS latency time in HCLKs of 2, 2.5, or 3.
The value is set at the factory depending on the DRAM installed. Do
not change the values in this field unless you change specifications of
the installed DRAM or the installed CPU.
DRAM CAS Latency This item controls the timing delay (in clock cycles) before the DRAM
starts a read command after receiving it.
RAS Active Time (tRAS) This item allows you to set the amount of time a RAS can be kept
open for multiple accesses. High figures will improve performance.
RAS Precharge Time (tRP) This is the duration of the time interval during which the Row Address
Strobe signal to a DRAM is held low during normal Read and Write
Cycles. This is the munimum interval between completing one read
or write and starting another from the same (non-page mode) DRAM.
Techniques such as memory interleaving, or use of Page Mode
DRAM are often used to avoid this delay. Some chipsets require this
parameter in order to set up the memory configuration properly. The
RAS Precharge value is typically about the same as the RAM Access
(data read/write) time.
RAS to CAS Delay (tRCD) This is the amount of time a CAS is performed after a RAS. This
lower the better, but some DRAM does not support low figures.
Current CPU Frequency 133 MHz Item Help
Current DRAM Frequency 200 MHz
DRAM Timing Control
[By SPD] Menu Level X
x DRAM CAS Latency 2.5T
x RAS Active Time (tRAS) 6T
x RAS Recharge Time (tRP) 3T
x RAS to CAS Delay (tRCD) 3T
Phoenix - AwardBIOS CMOS Setup Utilitye
DRAM Clock/Timing Control
KLIJ
: Move Enter: Select +/-/PU/PD: Value F10:Save ESC: Exit F1: General Help
F5: Previous Values F7: Optimized Defaults