Dominator Memory Timings

Taken from the Corsair http://www.houseofhelp.com/forums/showthread.php?t=54052

Dominator Qualification and Testing Updated 6-20-2007

Corsair has developed a methodology in-house for developing, qualifying, and testing memory for use in over clocking applications. Some common questions about this process are answered below, and details are given for testing for specific XMS product families.

Q: What does XMS mean, and what is the idea behind it?

A: We have taken to heart a few facts that over clockers have known for years:
1) Many integrated circuits are capable of operating much faster than their specified speed
2) Standards organizations by their very nature have a difficult time keeping up with market changes.

XMS, or eXtreme Memory Speed, is the process that Corsair uses to take ICs rated at one speed and verify/guarantee their operation at another speed. Since specifications have not been generated to accurately specify operating parameters, Corsair gives these parts an XMS rating. For example, since PC2400 does not exist according to any valid standards institution, Corsair parts are called XMS2400.

Q: How do you verify operation at the XMS speed?

A: In a nutshell, through extensive evaluation in our lab. In order to offer an XMS module, a RAM must be found which can run with adequate stability in multiple platforms at the XMS-rated speed. Testing is done using both Corsairs’ stress-testing fixture, as well as by running common benchmarks, applications programs, operating systems, and games. Parts are evaluated over voltage and temperature extremes to monitor stability. No XMS part is released until all criteria are met.

Q: How do you guarantee operation at the XMS speed?

A: XMS parts are a speed screen of Corsair's standard parts. They are 100% tested at the XMS-rated speed; parts that fall out of this test are tested at the standard rated speed. For example, XMS2400 modules are 100% tested at 300 MHz. Parts that do not meet this speed grade are then tested at PC2100. Specific testing parameters for various XMS products are given below.

Q: How do you program the SPD of XMS parts?

A: Programming the SPD of our XMS parts is a bit problematic. The industry-standard specifications for the SPD values of XMS parts are often not yet defined by JEDEC (the appropriate standards organization) when the parts are introduced. In order to maintain compatibility with the multitudes of motherboards and BIOS revisions out there, the SPD values are programmed at the fastest available parameters defined by JEDEC. The SPD values are defined in the matrix below. Note, though, that in ALL CASES the Corsair part number (which contains the XMS speed grade) is programmed into the SPD as well.





DDR2 Dominator
DDR2 XM2S6400C3DF EPP + JEDEC Values for PC2-6400C5
DDR2 XM2S6400C4D EPP + JEDEC Values for PC2-6400C5
DDR2 XM2S8500/C5D EPP + JEDEC Values for PC2-6400C5
DDR2 XM2S8888/C4DF EPP + JEDEC Values for PC2-6400C5
DDR2 XM2S9136C5D EPP + JEDEC Values for PC2-6400C5
DDR2 XM2S10000C5DF EPP + JEDEC Values for PC2-6400C5


DDR3 Dominator & DHX
DDR3 XMS3-1067C7DHX Custom Values for PC3-1067
DDR3 XM3S-1333C9DHX Custom Values for PC3-1333
DDR3 XM3S-1600C10DHX Custom Values for PC3-1600

Q: My XMS module does not work at the rated speed in my system. Why not?

A: There are many reasons why this can happen. Let me outline a few of them:

1) There are lots of motherboards out there, and we can only realistically evaluate/qualify a handful. You may have a motherboard that simply does not overclock well.
2) There is interaction between specific RAM manufacturers and specific motherboard manufacturers. Thus, for example, while EPoX boards might work best with RAM vendor A, Soyo boards might work better with RAM vendor B. Corsair strives to find the RAM that works most universally.
3) Other system components may not be overclockable. This may include the processor, chip set, PCI bus, IDE channel, etc.
4) The demands of today’s high end graphics cards and GHz processors the quality of your power supply has become increasingly important. Make sure you power supply make and model is approved by your motherboard manufacturer and/or your CPU manufacturer.

There are many sites on the web which can give you more reasons, tell you which boards are best for overclocking. To get an idea, go to your favorite search engine and search for "overclocking guide".

*Important Note* Unless stated otherwise, all testing is done with only one module at a time.


Testing parameters for Twinx/XMS2-6400C3DF:
Twin2x2048-6400C3DF Data Sheet

Motherboard make and model: Asus M2N32-SLI Premium/Deluxe
Each pair is tested and packaged together using the following settings:
AI Over Clock Tuner: Manual
CPU External Frequency: Manually set to 200MHz
DDR2 SDRAM Clock: Manually set to 800MHz
PCI Express Freq: Auto
PCI Freq: 33.33
Performance Mode: Standard
DRAM Timing Selectable: Manual
SDRAM CAS Latency: 3T
SDRAM RAS to CAS Delay (tRCD): 4T
SDRAM Row Precharge (tRP): 3T
SDRAM Active to Precharge Delay (tRAS): 9T
SDRAM Write Recovery Time: 5
Command Rate: 2T
DDR2 SDRAM Voltage: 2.4 V
CPU Core Voltage: Auto
FSB Termination V: 1.50 V
MCH Chipset V: 1.65V
ICH Chipset V: 1.20V
All other settings are motherboard defaults.
Maximum DDR2 recommended VDIMM: 2.4 Volts Dominator Version Only!

Testing parameters for Twinx/XMS2-6400C4D:
Twin2x2048-6400C4D Data Sheet

Motherboard make and model: Asus P5B, P5WD2 or M2N32-SLI Premium/Deluxe
Each pair is tested and packaged together using the following settings:
AI Over Clock Tuner: Manual
CPU External Frequency: Manually set to 200MHz
DDR2 SDRAM Clock: Manually set to 800MHz
PCI Express Freq: Auto
PCI Freq: 33.33
Performance Mode: Standard
DRAM Timing Selectable: Manual
SDRAM CAS Latency: 4T
SDRAM RAS to CAS Delay (tRCD): 4T
SDRAM Row Precharge (tRP): 4T
SDRAM Active to Precharge Delay (tRAS): 12T
SDRAM Write Recovery Time: 5
Write to Precharge Delay: 15 (If its Listed)
Command Rate: 2T
DDR2 SDRAM Voltage: 2.1
CPU Core Voltage: Auto
FSB Termination V: 1.50 V
MCH Chipset V: 1.65V
ICH Chipset V: 1.20V



Testing parameters for Twinx/XMS2-8500/C5D:
Twin2x2048-8500C5D Data Sheet

Motherboard make and model: Asus P5B or M2N32-SLI Premium/Deluxe Only!
Each pair is tested and packaged together using the following settings:
AI Over Clock Tuner: Manual
OC Operation: Disabled
NOS Operation: Disabled
CPU External Frequency: Manually set to 268 MHz
PCI CLK1: Auto
PCI CLK2: Auto
DDR2 Voltage control: 2.20V
CPU Core Voltage: Auto
CPU Multiplier: 10
DDR2 SDRAM Clock: Manually set to 800MHz
DRAM Timing Selectable: Manual
SDRAM CAS Latency: 5T
SDRAM RAS to CAS Delay (tRCD): 5T
SDRAM Row Precharge (tRP): 5T
SDRAM Active to Precharge Delay (tRAS): 15T
SDRAM Write Recovery Time: 5
1T/2T: 2T
A1 Clock Skew: Auto
CKE: Auto
CS/ODT:1.00X
ADD/CMD:1.00X
MEMCLK:1.00X
DATA: Auto
DQS: Auto
DRAM: Auto
All other settings are motherboard defaults.
Maximum DDR2 recommended VDIMM: 2.2 Volts

Testing parameters for Twinx/XMS2-8888/C4DF:
Twin2x2048-8888C4DF Data Sheet

Motherboard make and model: Asus M2N32-SLI Only!
Each pair is tested and packaged together using the following settings:
AI Over Clock Tuner: Manual
OC Operation: Disabled
NOS Operation: Disabled
CPU External Frequency: Manually set to 268 MHz
PCI CLK1: Auto
PCI CLK2: Auto
DDR2 Voltage control: 2.40V
CPU Core Voltage: Auto
CPU Multiplier: 10
DDR2 SDRAM Clock: Manually set to 800MHz
DRAM Timing Selectable: Manual
SDRAM CAS Latency: 5T
SDRAM RAS to CAS Delay (tRCD): 5T
SDRAM Row Precharge (tRP): 5T
SDRAM Active to Precharge Delay (tRAS): 15T
SDRAM Write Recovery Time: 5
1T/2T: 2T
A1 Clock Skew: Auto
CKE: Auto
CS/ODT:1.00X
ADD/CMD:1.00X
MEMCLK:1.00X
DATA: Auto
DQS: Auto
DRAM: Auto
All other settings are motherboard defaults.
Maximum DDR2 recommended VDIMM: 2.4 Volts

Testing parameters for Twinx/XMS2-9136C5D:
Twin2x2048-9136C5D Data Sheet

Motherboard make and model: EVGA 680I SLI Only!
Each pair is tested and packaged together using the following settings:
Advanced Chipset Features
FSB & Memory Config: Disabled
SLI Ready Memory: CPUOC Max
Memory Timings: Optimal
EPP Enabled yeilds these settings:
Memory Frequency: 1142 MHz
DDR2 Voltage control: 2.10V
SDRAM CAS Latency: 5T
SDRAM RAS to CAS Delay (tRCD): 5T
SDRAM Row Precharge (tRP): 5T
SDRAM Active to Precharge Delay (tRAS): 15T
SDRAM Write Recovery Time: 5

Maximum DDR2 recommended VDIMM: 2.1 Volts

Testing parameters for Twinx/XMS2-10000C5DF:
Twin2x2048-10000C5DF Data Sheet

Motherboard make and model: EVGA 680I SLI Only!
Each pair is tested and packaged together using the following settings:
Advanced Chipset Features
FSB & Memory Config: Disabled
SLI Ready Memory: CPUOC Max
Memory Timings: Optimal
EPP Enabled yeilds these settings:
Memory Frequency: 1250 MHz
DDR2 Voltage control: 2.40V
SDRAM CAS Latency: 5T
SDRAM RAS to CAS Delay (tRCD): 5T
SDRAM Row Precharge (tRP): 5T
SDRAM Active to Precharge Delay (tRAS): 18T
SDRAM Write Recovery Time: 5

Maximum DDR2 recommended VDIMM: 2.1 Volts

XMS3 DHX

Testing parameters for TWIN3X/XMS3-1067C7DHX:
TWIN3X2048-1067C7DHX Data Sheet Coming Soon

Motherboard make and model: ASUS P5K3 !
Each pair is tested and packaged together using the following settings:
Advanced
Jumper Free
AI Overclock: Manual
CPU Control: AUTO
FSB Frequency: 266 MHz
PCIE Frequency: AUTO
DRAM Frequency: DDR3-11067 MHz
DRAM Timings Control: Manual
CAS# Latency:___________7
RAS# to CAS# Delay:______7
RAS# Precharge:__________7
RAS# Activate to Precharge:20
DRAM Voltage:_________1.5V
All settings not listed should be left at AUTO or BIOS Default
Maximum DDR3 recommended VDIMM: 2.00 Volts


Testing parameters for TWIN3X/XMS3-1333C9DHX:
TWIN3X2048-1333C9DHX Data Sheet

Motherboard make and model: ASUS P5K3 !
Each pair is tested and packaged together using the following settings:
Advanced
Jumper Free
AI Overclock: Manual
CPU Control: AUTO
FSB Frequency: 266 MHz
PCIE Frequency: AUTO
DRAM Frequency: DDR3-1333 MHz
DRAM Timings Control: Manual
CAS# Latency:___________9
RAS# to CAS# Delay:______9
RAS# Precharge:__________9
RAS# Activate to Precharge:24
DRAM Static Read Control: Disabled
DRAM Dynamic Write Control: Disabled
CPU Spread Spectrum: Disabled
PCIE Spread Spectrum: Disabled
CPU Voltage:__________1.4500V
CPU PLL Voltage:_______1.6V
DRAM Voltage:_________1.5V
FSB Termination Voltage:_1.3V
North Bridge Voltage:____1.55V
All settings not listed should be left at AUTO or BIOS Default
Maximum DDR3 recommended VDIMM: 2.00 Volts


Testing parameters for TWIN3X/XMS3-1600C10DF:
TWIN3X2048-16000C10DF Data Sheet Coming Soon

Motherboard make and model: ASUS P5K3 !
Each pair is tested and packaged together using the following settings:
Advanced
Jumper Free
AI Overclock: Manual
CPU Ratio Control: AUTO
FSB Frequency: 400 MHz
PCIE Frequency: 100
DRAM Frequency: DDR3-1600 MHz
DRAM Timings Control: Manual
CAS# Latency:___________10
RAS# to CAS# Delay:______8
RAS# Precharge:__________8
RAS# Activate to Precharge:24
DRAM Static Read Control: Disabled
DRAM Dynamic Write Control: Disabled
CPU Spread Spectrum: Disabled
PCIE Spread Spectrum: Disabled
CPU Voltage:__________1.4500V
CPU PLL Voltage:_______1.6V
DRAM Voltage:_________1.5V
FSB Termination Voltage:_1.3V
North Bridge Voltage:____1.55V
All settings not listed should be left at AUTO or BIOS Default
Maximum DDR3 recommended VDIMM: 2.00 Volts

Edited by skyR - 22 Oct 2007 at 7:03pm