AMD SB750, 790GX user manual CPU Feature, Dram Configuration, CAS # Latency, RAS-to-CAS Delay

3-11-1 CPU Feature

Phoenix – AwardBIOS CMOS Setup Utility

CPU Feature

Virtualization	Enabled	Item Help
AMD K8 Cool & Quiet control	Disabled
TLB Check	Enabled
Advanced clock calibration	Disabled	Menu Level >
Value (ALL Cores)	2%
Value (Cores 0)	2%
Value (Cores 1)	2%
Value (Cores 2)	2%
Value (Cores 3)	2%

↑↓→← Move Enter:Select +/-/PU/PD:Value F10:Save ESC:Exit F1:General Help

F5:Previous Values F6:Fail-safe Defaults F7:Optimized Defaults

3-11-2 DRAM Configuration

Phoenix – AwardBIOS CMOS Setup Utility

DRAM Configuration

DRAM Latency(tcl)	Auto	Item Help
(Trcd)RAS to CAS R/W Delay	6 Clocks
(Trp) Row precharge Time	6 Clocks
(Tras)Minimum RAS Active Time	18 bus clocks
DRAM Command Rate	2T
CKE base Power dowe mode	Enabled
CKE BASED Powerdown	per channel
Memclock tri-slating	Disabled
Memory Hole Remapping	Enabled
Auto optimize Bottom IO	Enabled
*Bottom of 【31：24】IO space	DO
Bottom of UMA DDRAM [31:24]	FC
DDRII Timing Item	Disabled
Refresh Mode Select	Auto
Idle cycle limit	Auto
TwTr Command Delay	3 bus clocks
Trfc 0 for DIMM0	75ns
* Trfc 1 for DIMM 1	75ns
* Trfc 2 for DIMM 2	75ns
* Trfc 3 for DIMM 3	75ns
* (Twr) write Recovery Time	6 bus clock
		Menu Level >>
* (Trtp) Precharge Time	3 clocks
(Trc) Row cycle Time	26 bus clocks
Trc RAS to RAS Delay	5 clocks
Trcd RAS to CAS R/W Delay	6 clocks

↑↓→← Move Enter:Select +/-/PU/PD:Value F10:Save ESC:Exit F1:General Help

F5:Previous Values F6:Optimized Defaults F7:Standard Defaults

CAS # Latency

When synchronous DRAM is installed, the number of clock cycles of CAS latency depends on the DRAM timing. The settings are: Auto,3, 4 and 5.

RAS-to-CAS Delay

36