XMS Qualifications and TestingPost Date: 2007-08-05 |
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Kelly
Senior Member Digital Storm Customer Service Joined: 13 May 2008 Online Status: Offline Posts: 791 |
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Topic: XMS Qualifications and Testing Posted: 05 Aug 2007 at 12:16pm |
Stolen graciously from the corsair forums http://www.houseofhelp.com/forums/showthread.php?t=52351
XMS 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. Dont see your module or speed grade listed please check Archive XMS Settings XMS DDR1 Archive XMS Settings DDR2 DDR2 XM2S-4300C3_____Custom values for PC2-4300C3 DDR2 XM2S-5400_______Custom values for PC2-5400 DDR2 XM2S-5400UL_____Custom values for PC2-5400UL DDR2 XMS2-5400C4_____Custom values for PC2-5400C4 DDR2 XM2S-6400C3_____EPP + JEDEC Values for PC2-6400C5 DDR2 XM2S-6400C4_____EPP + JEDEC Values for PC2-6400C5 DDR2 XM2S-6400_______JEDEC Values for PC2-6400C5 DDR2 XM2S-8000UL_____Custom values for PC2-8000UL DDR2 XM2S-8500/C5____EPP + JEDEC Values for PC2-6400C5 DDR2 XMS2-6400C5DHX_JEDEC Values for PC2-6400C5 For Dominator DDR2 or DDR3 modules please see Dominator Qualifications and Testing! 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 over clock 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 over clock able. 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 over clocking. To get an idea, go to your favorite search engine and search for "over clocking guide". Q: I do not see the specific part that I have IE: XMS3200LLPT, why not? And what is the idea behind a slightly different part#? A: The PT at the end of the part# in this case CMX512-3200LLPT indicates the color of the heat spreader, and would be a cosmetic change! This has no bearing on the memory or settings only the color. Please see What does C2, LL, PT, R or RE stand for in the part#? Or Archive XMS Settings *Important Note* Unless stated otherwise, all testing is done with only one module at a time. XMS DDR1 Archive XMS Settings XMS DDR2 Testing parameters for Twin2x1024-4300C3: Twin2x1024-4300C3 Data Sheet Motherboard make and model: ABIT AA8 Durramax and/or Asus P5AD2 Premium Each pair is tested and packaged together using the following settings: CPU External Frequency: Manually set to 200MHz DDR2 SDRAM Clock: Manually set to 533MHz DRAM Timing Selectable: Auto Yields the following timings SDRAM CAS Latency: 3T SDRAM RAS to CAS Delay (tRCD): 3T SDRAM Row Precharge (tRP): 3T SDRAM Active to Precharge Delay (tRAS): 8T DDR2 SDRAM Voltage: 1.9 NB Voltage 1.9 Volts (On Abit AA8 Only) All other settings are motherboard defaults. Maximum DDR2 recommended VDIMM: 2.1 Volts Testing parameters for Twinx/XMS2-5400C4: CM2X256-5400C4 Data Sheet CM2X512-5400C4 Data Sheet TWIN2X1024-5400C4 Data Sheet Motherboard make and model: ABIT AA8 Durramax and/or Asus P5AD2 Premium Each pair is tested and packaged together using the following settings: CPU External Frequency: Manually set to 250MHz DDR2 SDRAM Clock: Manually set to 533MHz DRAM Timing Selectable: Auto Yields the following timings SDRAM CAS Latency: 4T SDRAM RAS to CAS Delay (tRCD): 4T SDRAM Row Precharge (tRP): 4T SDRAM Active to Precharge Delay (tRAS): 12T DDR2 SDRAM Voltage: 1.9 NB Voltage 1.9 Volts (On Abit AA8 Only) All other settings are motherboard defaults. Maximum DDR2 recommended VDIMM: 2.1 Volts Testing parameters for Twinx/XMS2-5400UL: Twin2x1024-5400UL Data Sheet Testing parameters for CM2X512A-5400UL: Twin2x1024-5400UL Data Sheet Motherboard make and model: Asus P5AD2-E Premium Each pair is tested and packaged together using the following settings: AI Over Clock Tuner: Manual CPU External Frequency: Manually set to 226MHz DDR2 SDRAM Clock: Manually set to 678MHz 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): 3T (Revised 6/27/2005) SDRAM Row Precharge (tRP): 2T SDRAM Active to Precharge Delay (tRAS): 8T SDRAM Write Recovery Time: 4 DDR2 SDRAM Voltage: 2.1 Chipset Core Voltage: 1.7 Volts All other settings are motherboard defaults. Maximum DDR2 recommended VDIMM: 2.1 Volts Testing parameters for Twinx/XMS2-6400C3: Twin2x2048-6400C3 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 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: 2.1 V Advanced voltage control CPU Vcore offset:_Disabled DDR2 Termination: 0.5x CPU to NB HT:____1.200V NB to SB HT:_____AUTO NB Core/PCI-E:___AUTO SB Core/PCI-E:___AUTO SB Standby core:_+1.500V Output driver control CKE:______AUTO CS/ODT:__1.00X ADD/CMD:_1.00X MEMCLK:__1.00X All other settings are motherboard defaults. Maximum DDR2 recommended VDIMM: 2.1 Volts Testing parameters for Twinx/XMS2-6400C4: Twin2x2048-6400C4 Data Sheet Motherboard make and model: Asus 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 it's Listed) Command Rate: 2T DDR2 SDRAM Voltage: 2.1 Advanced voltage control CPU Vcore offset:_Disabled DDR2 Termination: 0.5x CPU to NB HT:____1.200V NB to SB HT:_____AUTO NB Core/PCI-E:___AUTO SB Core/PCI-E:___AUTO SB Standby core:_+1.500V Output driver control CKE:______AUTO CS/ODT:__1.00X ADD/CMD:_1.00X MEMCLK:__1.00X Chipset Core Voltage: Auto All other settings are motherboard defaults. Maximum DDR2 recommended VDIMM: 2.1 Volts Testing parameters for Twinx/XMS2-6400: Twin2x1024A-6400 Data Sheet Twin2x2048-6400 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: 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 Write to Precharge Delay: 15 (If it's Listed) Command Rate: 2T DDR2 SDRAM Voltage: 1.9 Advanced voltage control CPU Vcore offset:_Disabled DDR2 Termination: 0.5x CPU to NB HT:____1.200V NB to SB HT:_____AUTO NB Core/PCI-E:___AUTO SB Core/PCI-E:___AUTO SB Standby core:_+1.500V Output driver control CKE:______AUTO CS/ODT:__1.00X ADD/CMD:_1.00X MEMCLK:__1.00X All other settings are motherboard defaults. Maximum DDR2 recommended VDIMM: 2.1 Volts Testing parameters for Twinx/XMS2-8000UL: Twin2x1024-8000UL Data Sheet Motherboard make and model: Asus P5WD2 Premium/Deluxe Each pair is tested and packaged together using the following settings: AI Over Clock Tuner: Manual CPU External Frequency: Manually set to 250MHz DDR2 SDRAM Clock: Manually set to 1000MHz PCI Express Freq: Auto PCI Freq: 33.33 CPU Core Voltage: Auto FSB Termination V: 1.5 Volts MCH Chiset V: 1.65 Volts ICH Chiset V: 1.20 Volts Performance Mode: Standard DRAM Timing Selectable: Manual SDRAM CAS Latency: 5T SDRAM RAS to CAS Delay (tRCD): 4T SDRAM Row Precharge (tRP): 4T SDRAM Active to Precharge Delay (tRAS): 9T SDRAM Write Recovery Time: 5 DDR2 SDRAM Voltage: 2.2 Chipset Core Voltage: Auto All other settings are motherboard defaults. Maximum DDR2 recommended VDIMM: 2.1 Volts, However this DDR2 module would be the only one rated at 2.2 Volts Max. Testing parameters for Twinx/XMS2-8500/C5: Twin2x1024-8500 Data Sheet Twin2x2048-8500C5 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 OC Operation: Disabled NOS Operation: Disabled CPU External Frequency: Manually set to 268 MHz PCI CLK1: Auto PCI CLK2: Auto DDR2 Voltage control: 2.200V 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 Advanced voltage control CPU Vcore offset:_Disabled DDR2 Termination: 0.5x CPU to NB HT:____1.200V NB to SB HT:_____AUTO NB Core/PCI-E:___AUTO SB Core/PCI-E:___AUTO SB Standby core:_+1.500V Output driver control CKE:______AUTO CS/ODT:__1.00X ADD/CMD:_1.00X MEMCLK:__1.00X All other settings are motherboard defaults. Maximum DDR2 recommended VDIMM: 2.1 Volts, However this DDR2 module would be the only one rated at 2.2 Volts Max. DDR2 XMS2DHX Testing parameters for TWIN2X/XMS2-6400: Twin2x2048-6400C5DHX 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 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 Write to Precharge Delay: 15 (If it's Listed) Command Rate: 2T Advanced voltage control CPU Vcore offset:_Disabled DDR2 Termination: 0.5x CPU to NB HT:____1.200V NB to SB HT:_____AUTO NB Core/PCI-E:___AUTO SB Core/PCI-E:___AUTO SB Standby core:_+1.500V Output driver control CKE:______AUTO CS/ODT:__1.00X ADD/CMD:_1.00X MEMCLK:__1.00X DDR2 SDRAM Voltage: 1.9 All other settings are motherboard defaults. Maximum DDR2 recommended VDIMM: 2.1 Volts Testing parameters for TWIN2X4096-6400C5DHX: Testing parameters for QUAD2X4096-6400C5DHX: TWIN2X4096-6400C5DHX Data Sheet QUAD2X4096-6400C5DHX 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/(266Mhz for Intel) DDR2 SDRAM Clock: Manually set to 800MHz PCI Express Freq: Auto PCI Freq: 33.33 Performance Mode: User Define/Manual 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 Write to Precharge Delay: 15 (If it's Listed) Command Rate: 2T DDR2 SDRAM Voltage: 1.9 Advanced voltage control CPU Vcore offset:_Disabled DDR2 Termination: 0.5x CPU to NB HT:____1.200V NB to SB HT:_____AUTO NB Core/PCI-E:___AUTO SB Core/PCI-E:___AUTO SB Standby core:_+1.500V Output driver control CKE:______AUTO CS/ODT:__1.00X ADD/CMD:_1.00X MEMCLK:__1.00X Chipset Core Voltage: Auto All other settings are motherboard defaults. Maximum DDR2 recommended VDIMM: 2.1 Volts Edited by skyR - 22 Oct 2007 at 7:03pm |
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Larry
Senior Member Joined: 03 Aug 2007 Online Status: Offline Posts: 167 |
Quote Reply Posted: 05 Aug 2007 at 3:32pm |
Thanks for the information. Can one really see a speed difference say between 2GB of memory at 800mhz as compared to the 1066mhz? How dramatically does this affect gameplay? |
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Kelly
Senior Member Digital Storm Customer Service Joined: 13 May 2008 Online Status: Offline Posts: 791 |
Quote Reply Posted: 05 Aug 2007 at 3:50pm |
it doesn't really affect anything with the games. But where it does make a difference is how the os performs. Think of it as a road. The wider the road, the more cars can travel at any given time and how fast each car can drive.
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