Matching RAM not working in Dual Channel.

By Shaw23 ยท 35 replies
Apr 18, 2007
  1. A couple of months ago I bought a new motherboard, processor, PSU and a stick of 1GB ram. I didnt know the MB was dual channel and I didnt understand the concept of it at the time so I didnt bother with getting matching pairs. Recently I ordered a matching stick which had the exact same Tiger Direct Part number. I just got it today and plugged it in and it wouldnt work in Dual channel, it works in single just fine though. I have CUPZ and the only differences that I can see are as follows:

    New RAM Manufacturer:"7F7F7F7F7F3E0000"
    Older Ram Manufacturer:"PDP Systems"

    Timings table for the New RAM has 3 speeds (133/166/200) and the older has 2 speeds(166/200), attaced is the .txt dump from CPUZ, please see the Memory SPD section.

    I called the ULTRA Tech Support and the guy said they should be compatible and he gave me an incompatibility code to return and try a different chip. I thought maybe someone here might have some info to help me.

    Another question, if the chips aren't compatible then should I send the older one back in the new ones package to get a more updated one, or should I send the new one back?


    Attached Files:

  2. sghiznaneck

    sghiznaneck TS Maniac Posts: 403

    First question is what mobo do you have. Second question is did you place the sticks of RAM in the correct slots?? Your mobo manual should tell you which slots to use.
  3. Shaw23

    Shaw23 TS Enthusiast Topic Starter Posts: 62

    The best way to tell you about the mobo is to give you the actual link to where I bought it so here it is. It only has 2 slots so they are in the correct ones.

    Here is the link to the RAM. I dont remember seeing it the first time when I bought the first stick but this time it has the CAS Latency listed in the specs. Is it possible that they updated the chip in the month or two and now it isny compatible with the first one I bought?

    Maybe it would be best to send back the first one?
  4. sghiznaneck

    sghiznaneck TS Maniac Posts: 403

    That may be the best solution and have it replaced with a match for the other stick. RAM is a tricky thing, especially the dual channel. If they aren't a perfect match, they will either slow way down or not work at all.
  5. Shaw23

    Shaw23 TS Enthusiast Topic Starter Posts: 62

    Thanks for the comments. The CAS Latency on the first chip is 3-3-3-8 and the new one is 3-4-4-8. Is this why is isnt working? Also, if I send the first one back on the incompatibility number, would they know it was a different chip or would they just think it wasnt programmed right?
  6. Tedster

    Tedster Techspot old timer..... Posts: 6,002   +15

  7. CMH

    CMH TechSpot Chancellor Posts: 2,039   +9

    I think the easiest and best way of doing this would be to get an exact pair for your old RAM. Would have been alot better if you'd have bought matching pairs from the start (of course, I realise budget issues are there, but RAM is cheap...)

    If you're adventurous, you might want to change the timings so that they match, it MIGHT help, although I've never bought anything but matching pairs ever since Dual Channel came out....
  8. Shaw23

    Shaw23 TS Enthusiast Topic Starter Posts: 62

    Ted, I read through the thread you posted and the one linked to it but did not find help for me. Thanks for the useful and informative link though. Or were you telling me that is where I should be seeking help? I am not real new to computers although the very in depth stuff is a bit tricky for me still. I know the RAM is compatible with my system as it is working fine with no problems except dual channel... and I thought I was ordering the exact same part from the exact same vendor.

    The thing I am wondering is weather or not the timings have to match on both sticks for dual channel and if you can adjust the timings on just one stick. If you have looked at my text attachment from CPUZ the timings on both chips match at 166Mhz but not 200Mhz.

    CMH, I tried to get a stick that matched my first one but the one I just got evidentally dont match(I dont think), if I sent the newest one back what would be the odds of getting a match to the older one. Also, would it be easier to get a match if I would send back the one that is a couple months old for another one... or do you think the vendor would know that it wasn't the same exact chip (I do have a non-compatibility code from the manufacturer for an exchange).
  9. CMH

    CMH TechSpot Chancellor Posts: 2,039   +9

    They should know if you sent the wrong part back, or else I'd be buying top end RAM, and when RMAing, send back some Value RAM....

    In this case, I'd say you should get in contact, and tell them that the RAM wasn't a perfect match, and specifically mention that it will not run dual channel. If you did ask them for a perfect match to start with, then I believe they should be obligated to make sure that the RAM they sent you matched your old one (which means they might either refund your money, replacing your new RAM, or replace both RAM, although they'd probably just refund your money).
  10. Shaw23

    Shaw23 TS Enthusiast Topic Starter Posts: 62

    Well the reason I thought I might be able to do that was because it was the same vendor, same brand, same size, same speed, same part number everything matched, exept as I now know... the timings. I didnt look into detail at it yet but the stickers on the sticks looked the same, it was in the same package. But if you dont think it is very possible to get by with then I probably wont try it.
  11. captaincranky

    captaincranky TechSpot Addict Posts: 12,967   +2,524

    This may sound stupid.....

    I downloaded the manual to this board, and nowhere does it make mention that it actually is dual channel RAM. It says,"supports 2 DDR devices", no more.
  12. Shaw23

    Shaw23 TS Enthusiast Topic Starter Posts: 62

    That does not sound stupid. I looked through the manual again and I didnt not see it mention dual channel either. The reason I thought it was Dual channel was Tiger Direct said it was. Here is the exact link I ordered it from and it says it is dual channel in the description of "Memory Expansion" about 2/3 down the page. The actual text it has is:
    Memory Expansion
    The P4MSD-800 provides 2 DIMM sockets using Dual Channel 184-pin DDR with a total capacity of up to 2GB. You can install DDR 266/333/400MHz Memory.

    I guess maybe I should call the mobo tech support to verify that it really is dual channel? Maybe Tiger Direct made a typo?

    The item I bought from Tiger Direct was a CPU/Mobo combo. On the link that I ordered the combo from there is a link under the Mobo and the CPU to go to individualized pages for each. Here is the one for the Mobo and here is what it list for the memory on the individualized page:
    Memory Expansion
    The P4MSD-800 provides 2 DIMM sockets using 184-pin DDR with a total capacity of up to 2GB. You can install DDR 266/333/400MHz Memory.

    Maybe Tiger Direct "Hosed" me.
  13. howard_hopkinso

    howard_hopkinso TS Rookie Posts: 24,177   +19

    Hello and welcome to Techspot.

    I believe you`re mobo doesn`t support dual channel ram operation. See HERE for specs etc.

    I can`t see(unless I`ve missed it), where it says on the Tiger Direct site, that the mobo is dual channel capable.

    But if that`s what they said, you should contact them and show them the error of their ways.

    Regards Howard :wave: :wave:
  14. Shaw23

    Shaw23 TS Enthusiast Topic Starter Posts: 62

    Thank you everyone for your time and suggestions I wouldnt have realized the problem if I wouldnt have posted here, and I would have been looking for days.

    Howard, I am not sure if you are really interested in seeing on Tiger Direct where it says it is dual channel or not, but if you are then click here and scroll down about 2/3 of the page to the section titled "Memory Expansion", that is where it is at.

    I guess I know that in the future I will not be able to rely on Tiger Directs listed specs and I should research through the manufacturers. I am not sure what they will do about the error, if anything at all. But maybe I will let you know how it turns out.
  15. howard_hopkinso

    howard_hopkinso TS Rookie Posts: 24,177   +19

    Yes, I`ve seen it now. It does seem that Tiger Direct has got it wrong.

    I think you should definitely contact them and see what they say about it.

    Good luck.

    Regards Howard :)
  16. Shaw23

    Shaw23 TS Enthusiast Topic Starter Posts: 62

    I have been looking around on Tiger direct and just noticed this sentence: "TigerDirect is not responsible for typographical or photographical errors." Go figure, I guess I will find out tomorrow. Thanks again.

    ZWERVER TS Rookie Posts: 55

    Mach Speed P4MSD-800 Via Socket 775 MicroATX Motherboard and an Intel Pentium D 830 3.0GHz OEM Processor

    Technology up to 3.8GHz at 533 and 800MHz FSB. Based on the VIA P4M800 chipset, the Mach Speed P4MSD-800 supports up to 2 DDR memory modules at 133/166/200 MHz up to 2GB
  18. Shaw23

    Shaw23 TS Enthusiast Topic Starter Posts: 62

    SOrry but I dont get what you are saying.

    ZWERVER TS Rookie Posts: 55

    Try to look in bios, are u able to manualy change DDR clock rate?, try to test your hatdware with other test programms like DR Hardware or Sisoft sandra. U can start also benchmarks of RAM data bandwidth. Just look of u get a same results. Succes

    I have just checked it in other pc, actually CPU-Z gives u information correct, but that it''s seem to be for single channel. so dual is 2x200=400
  20. Tedster

    Tedster Techspot old timer..... Posts: 6,002   +15

    if your CL is different or timings are different, then obviously your ram is not matched.
  21. captaincranky

    captaincranky TechSpot Addict Posts: 12,967   +2,524

    We''ll Never Know.....

    Tiger Direct states that this motherboard is no longer available, and has deleted the tabbed pages. the only page still available is the first page. I'm uploading a screen cap from the site, make of it what you will.
  22. Shaw23

    Shaw23 TS Enthusiast Topic Starter Posts: 62

    As stated before, here is where I ordered it Mobo from... I ordered the Mobo/CPU combo, and for what it is worth I attached a screen shot of the attached page.

    I think the issue at hand is they have conflicting specs. I havent been able to try and contact anyone yet though.

    Attached Files:

  23. captaincranky

    captaincranky TechSpot Addict Posts: 12,967   +2,524

    Ouch, now I have a headache.....

    I would swear that I hit on your link, this because I'm too lazy to start over. Also, I swear that I didn't photoshop that screen cap. So.....? I went back and got the same result you did, on the second try.
    Something anecdotal: I just purchased an EVGA 7600GT graphics card (model 550, they have 3 7600GTs). Both Neweggs' site and EVGAs' site state that this card requires a 350 watt power supply. The card arrived with the system requirements on the box stating it requires a 400 watt PSU. I ordered it because of the system requirements of a 350 watt PSU, since if I purchased the higher overclocked card, it wanted a 400 watt PSU. No harm, no foul, since there's a 400 watt PSU in my case anyway. I thought it might be nice to have the wiggle room of an oversized PSU. As far as assigning blame here,
    I think Newegg an I are the victims. In your case, um, player to be named later.

    This is too late to do anything about, but it bears some thought for the future. I would never buy a motherboard with only 2 RAM sockets, even if it supported dual-channel RAM and 4 GB of RAM. It makes no monetary sense to do this. Suppose you have a 4 socket board with 1 GB installed (2 512s), if you wanted 2 GB total, you would just go out and buy 2 more 512s, and there's your deuce. With a 2 socket board you take out the 2 512s, and must buy a full 2 GB kit for the upgrade. With SOME boards (Intel in particular) you could move the 2 512s to 1 channel, and simply add a 1 GB DIMM to the second channel. This is saving a fair amount of money. Then if you wanted 3 GB of RAM, just split the 512s back to 1 in each channel and buy ONLY 1 more 1 GB stick. Now you have as much as a normal 32 bit OS can recognize. Many people spring for 2 GB on the first pass, then buy 2 GB more for the upgrade, then complain bitterly when the 4GB is not recognized. At current US prices, you've saved $65.00 or so and you board is full.

    Now, a 2 socket board which could recognize 4 GB of RAM would require purchasing 2 GB DIMMs at about $200.00 (USD) a pop. This is true in many of the new 4 socket boards which will recognize 8 GB of RAM, which to fill would require on expenditure of $800.00 or so to fill it to capacity.

    Please forgive the the editorial part of this.
  24. Shaw23

    Shaw23 TS Enthusiast Topic Starter Posts: 62

    I am getting a headache also.

    I do understand what you are saying about 2 port vs. 4 port and it makes since, I will take this into consideration in the future.

    I just called MACH Speed Tech support and they said that the motherboard is for sure dual channel capable. I asked why it isnt listed in the specs on their page and he said it is becuase dual channel is becoming an industry standard and is starting to be left out of the specs on new boards.
  25. captaincranky

    captaincranky TechSpot Addict Posts: 12,967   +2,524


    That's bizarre in the world of advertising....underreporting.

    This takes you back to your original theory of incompatibility. Bear in mind it doesn't take very much asymmetry to cause a board to drop out of dual channel operation.

    My question is this, did the board actually recognize all 2 GB? If so, you've actually fared better than many, although I understand that this would be of little comfort.

    Again I know that this is of little comfort, but at the moment the bottom has dropped out of RAM pricing. A worst case scenario is springing for a matched set of 2 1GB DIMMs.
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