Neuron Posted May 25, 2014 Share Posted May 25, 2014 I post a quote from the F.A.Q. thread Archive XMS Settings Here!. Note, though, that in ALL CASES the Corsair part number (which contains the XMS speed grade) is programmed into the SPD as well. XMS Specification_____SPD Values XMS2700C2________JEDEC PC2700 values XMS2700LL________Custom values XMS3000__________JEDEC PC2700 values XMS3200__________JEDEC PC3200 values XMS3200C2________JEDEC PC3200 values In XMS3200C2, for example, the part number indicates CL=2, right? And you say that the part number is programmed into the SPD. Then why the SPD for this one is "JEDEC PC3200" when JEDEC does not have CL=2 ? JEDEC PC3200 specifies these timings: 2.5-3-3 3-3-3 3-4-4 How can I know the SPD timings? Link to comment Share on other sites More sharing options...
emissary42 Posted May 25, 2014 Share Posted May 25, 2014 Can you please show a CPU-Z SPD screenshot of your kit? Link to comment Share on other sites More sharing options...
Administrators Technobeard Posted May 25, 2014 Administrators Share Posted May 25, 2014 The SPD isn't the rated speed. I believe on most (if not all) DDR1 kits the SPD was 3-4-4-8. Link to comment Share on other sites More sharing options...
Neuron Posted May 25, 2014 Author Share Posted May 25, 2014 Well I found this post, SPD Values, that has the same topic. As it comes out, this state by ram guy, "... in ALL CASES the Corsair part number is programmed into the SPD as well.", is totally wrong and also very misleading! The truth is, it is right for all cases EXCEPT C2. Where the SPD for dimms with a C2 suffix is either 3 or 2.5 and, as I know so far, you have no way to find witch one it is before you buy the dimm (or find someone who already bought it). Also, the sentence right before that can be confusing. It says "... the SPD values are programmed at the fastest available parameters defined by JEDEC." while most XMS dimms have Custom values. And in the case of C2 the possible CL=3 is not the fastest defined by JEDEC, CL=2.5 is the fastest for DDR400. So, @emissary42 I know how to use CPU-z, I just don't know how to find the SPD CL for a C2 dimm before I buy it. @Technobeard In the link I gave, kilroy67 found 3-3-3-8 and 2.5-3-3-8 so the 3-4-4-8 can't be the standard. The "funny" thing is that these are the timings for a different version of the same dimm (same p/n). I just have to suppose that this happens only in DDR1 and not in DDR2 and 3. And the confusing text is there because they copied and paste the updated text from DDR2 and 3 to the old DDR1 post. I speak in present tense cause I still buy this stuff for my prehistoric pc. Link to comment Share on other sites More sharing options...
Administrators Technobeard Posted May 25, 2014 Administrators Share Posted May 25, 2014 The label on the module will tell you what the timings are. Link to comment Share on other sites More sharing options...
Neuron Posted May 25, 2014 Author Share Posted May 25, 2014 The timings indication in the C2 suffixed DDR1 modules that I have seen show the rated timings, not the default (the SPD). for example: http://images10.newegg.com/ProductImage/20-145-560-01.jpg http://cache.osta.ee/iv2/auctions/1_1_15781987.jpg Can you find the default timings? (edit: I put more clear photos) Link to comment Share on other sites More sharing options...
Synthohol Posted May 25, 2014 Share Posted May 25, 2014 ooh!! ive had a few of those sticks! check the ver# if they are BH5 i ran 2,2,2,5 for a long time at 220. and 2,2,2,11 if you have any stability issues. i miss that ram!! Link to comment Share on other sites More sharing options...
Neuron Posted May 25, 2014 Author Share Posted May 25, 2014 Hehe. Well, we talk about the SPD values here, not the rated, and not the lowest possible. Just the default. Link to comment Share on other sites More sharing options...
Administrators Technobeard Posted May 25, 2014 Administrators Share Posted May 25, 2014 Right, those are the rated timings on the label. Question: Why do you want to know the default ratings of modules without putting them in your system? Link to comment Share on other sites More sharing options...
emissary42 Posted May 25, 2014 Share Posted May 25, 2014 As it comes out, this state by ram guy, "... in ALL CASES the Corsair part number is programmed into the SPD as well.", is totally wrong and also very misleading! The truth is, it is right for all cases EXCEPT C2.You quoted RAM Guy about the part number being programmed into the SPD. I might not have had every kit out there, but for all of my C2 parts that was true. E.g. for dozens of TWINX2048-3200C2 it looked like that: http://www.abload.de/img/spd_2x1gb_corsairzsn.jpg Also, the sentence right before that can be confusing. It says "... the SPD values are programmed at the fastest available parameters defined by JEDEC." while most XMS dimms have Custom values. And in the case of C2 the possible CL=3 is not the fastest defined by JEDEC, CL=2.5 is the fastest for DDR400. I found a quote that differs slightly about that: "All of our XMS modules that end with a "C2" Designation will have their SPD set to JEDEC defined values for the specific IC we use to make that part." (Source). I guess CL3 is a safer way to go for kits, that would otherwise not work at CL2.5 with default memory voltage. Where the SPD for dimms with a C2 suffix is either 3 or 2.5 and, as I know so far, you have no way to find witch one it is before you buy the dimm (or find someone who already bought it). You had to manually set CL2 with either of those, so it doesn't really matter if it is CL2.5 or CL3 in the SPD? Link to comment Share on other sites More sharing options...
Neuron Posted May 26, 2014 Author Share Posted May 26, 2014 @Technobeard I want to know the defaults because I like the stuff that I buy to work as advertised without the need from me to tweak them. Like All other Corsair DDR1 modules. for dozens of TWINX2048-3200C2 it looked like that: LOL now I see that! So he talks about the p/n itself! Then what he says is not wrong, he just doesn't say what he should. He links you there (your 2nd quote) to find out when the p/n info agrees with the SPD and he doesn't even mention it, but he rather says that the p/n itself is written in the SPD. I found a quote that differs slightly about that: "All of our XMS modules that end with a "C2" Designation will have their SPD set to JEDEC defined values for the specific IC we use to make that part." (Source). He says that in a member's post, somewhere. He throws a link that would explain everything. The link is broken (now), and if you find the source, the info is not there. But he said it, right? I guess CL3 is a safer way to go for kits, that would otherwise not work at CL2.5 with default memory voltage. Yes that's why there are the C3 (not suffixed) modules. You had to manually set CL2 with either of those, so it doesn't really matter if it is CL2.5 or CL3 in the SPD? Did you have to manually set the CL to other (not C2 suffixed) dimms too? @emissary42 Now that you mentioned your C2 parts, can you find a relation between the version and SPD CL? I mean above which version the CL=2.5. I saw there are lists about p/n and chip correspondence, maybe that's the clue. Better chip -> CL=2.5. Link to comment Share on other sites More sharing options...
Administrators Technobeard Posted May 26, 2014 Administrators Share Posted May 26, 2014 Unless the rated timings are 3-4-4-8, you'll have to tweak the BIOS. Fixed the link - http://forum.corsair.com/forums/showthread.php?t=38144 The DDR1 IC list is here: http://forum.corsair.com/forums/showthread.php?t=44365 Link to comment Share on other sites More sharing options...
emissary42 Posted May 26, 2014 Share Posted May 26, 2014 Did you have to manually set the CL to other (not C2 suffixed) dimms too? I had to manually set specified values for all my O#Z DDR3 kits, ever. They just didn't care to put in a profile with specified speeds / timings. The good thing is, you did learn a lot about memory timings and their interactions xD Now that you mentioned your C2 parts, can you find a relation between the version and SPD CL? I mean above which version the CL=2.5. I saw there are lists about p/n and chip correspondence, maybe that's the clue. Better chip -> CL=2.5. For overclocking @ CL2 you probably would want Winbond BH5/BH6: http://forum.corsair.com/forums/showthread.php?t=44365 There isn't anything else that came close to it in regards of low latency. Some kits could do CL1.5 just fine. They need lots of voltage however, sometimes more then even the more decent boards could provide (thats why we had volt mods and RAM boosters^^). Link to comment Share on other sites More sharing options...
Neuron Posted May 28, 2014 Author Share Posted May 28, 2014 @Technobeard Thank you for the IC list. I managed to find, from a members post, that CMX1024-3200PT v3.1 probably defaults to cl3. It "supposedly uses Infineon B-5 IC's" as he says, and these chips are also used in unsuffixed (cl3) models from the list. Yes this is what someone has to do in order to find the defaults, yet not the exact ones but the most possible. @emissary42 No you didn't have to manually set the timings to other dimms, in order to much the rated values, because they were already set to the rated values. You just wanted to overclock them (more). I mean C2 is just an exception (where defaults not equal to rated), and this should be clearly mentioned somewhere. Yes it seems like you have to become a corsair guru to find one of the most basic specs. Sure I learned some stuff. Link to comment Share on other sites More sharing options...
emissary42 Posted May 28, 2014 Share Posted May 28, 2014 No you didn't have to manually set the timings to other dimms, in order to much the rated values, because they were already set to the rated values. Nope, thats not the case. See this: http://abload.de/img/e42OCZreaperhpclv21333pu6u.png This is a kit specced by OCZ for DDR3-2133 7-10-7-27 1.65V, but it will only ever run DDR3-1066 CL7 1.50V without manually inputting every single timing and the appropriate memory divider + Vdimm. It was rather annoying, because finding the correct secondary timings can be quite time consuming on higher end kits. Thank god, Corsair picked up on advanced memory profiles (esp. XMP) really fast. So Corsair buyers just have to flip a switch in the BIOS and they're done. Yes it seems like you have to become a corsair guru to find one of the most basic specs. Sure I learned some stuff. Back in the DDR1 days, almost every hardware community out there had a memory list for certain IC types. There were some other manufacturers that made it even harder / next to impossible to identify the ICs used and actual specifications (timings) without dismantling the heatspreaders and/or plugging the kit. You didn't necessarily need to be a guru yourself, just know where to look for the information. Maybe some of those threads are still available. If your still looking for a specific information, might as well just give it a shot. Link to comment Share on other sites More sharing options...
Neuron Posted May 29, 2014 Author Share Posted May 29, 2014 Nope, thats not the case. I talk about DDR1. Isn't SPD = rated, for all except C2 modules? Isn't "Custom values" = rated values here? XMS Specification_____SPD Values XMS2700C2________JEDEC PC2700 values XMS2700LL________Custom values XMS3000__________JEDEC PC2700 values XMS3200__________JEDEC PC3200 values XMS3200C2________JEDEC PC3200 values XMS3200LL________Custom values XMS3200XL________Custom values XMS3500LLPro______Custom values XMS3500C2________JEDEC PC3200 values XMS3700__________Custom values for PC3700* XMS4000__________Custom values for PC3700* XMS4400__________Custom values for PC3700* XMS4400C25_______Custom values for PC3700* Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.