9200 RAM slots WHITE & BLACK why?

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9200 RAM slots WHITE & BLACK why?

  • I can't be the first to notice it but I can't find any previous thread on the subject. My question is: There are four RAM sots on the DIMENSION 9200 Motherboard - two are black and two are white. What's the significance of this (and why won't my upgraded RAM work howsoever I configure it???)
     
    Thanks to anyone who knows the answer.
     
    Bill
  • The significance is the memory must be installed in matching pairs.  If the memory isn't working most likely it's not compatible with your system.  Your best bet is go to Crucial and use their Memory Advisor tool.
     
     
     
  • Here is a link describing the memory slots and installing memory:

    http://support.dell.com/support/edocs/systems/dim9200/en/SM_EN/parts.htm#wp1462641

    Memory does not need to be installed in pairs. It only needs to be installed in pairs to have dual channel mode work.

    You should put a matched pair in the white slots and another matched pair in the black slots to get dual channel mode.

    I think the Dell docs are in error about the channels, though. Each pair accesses both channels (one stick for each channel) in order to get dual channel mode. They seem to imply that one pair is one channel. The whole idea of dual channel mode is that there are two memory channels in parallel. Putting matching sticks in each channel allows parallel accesses to occur.

    Why you RAM does not work is another issue. Russell_314 may be correct or possibly the RAM is bad.

    Peter
  • I've seen posted in the boards here that IF u do NOT install in MATCHED pairs that u will lose 10 - 15 %, so that's y the matched pairs r recommended.

    The WHITE slots wud b 1 pair
    The BLACK slots are ur other pair

  • musiclover28463 wrote:
    I've seen posted in the boards here that IF u do NOT install in MATCHED pairs that u will lose 10 - 15 %, so that's y the matched pairs r recommended.




    I just ran some tests. For a CPU intensive job that takes around 5 minutes to complete, timed the job under a variety of conditions:

    One core fully utilized:
    1. Dual channel (3G): 5:23 (+0%)
    2. Single channel (2.5G): 5:24 (+.3%)

    Both cores fully utilized
    1. Dual channel (3G): 6:17 (+0%)
    2. Single channel (2.5G): 6:26 (+2.3%)

    My machine is a 9200 with C2D 2.4G 4M L2 cache, 533M RAM. Note that running in single channel mode only slows down by .3% and 2.3% for one core and two cores fully utilized. Not that big a difference!

    I also tested 533M vs. 667M RAM. The slowdown for using 533M is 2% for one core utilized and 4% for both cores utilized. More significant than dual channel mode.

    Peter

  • PETER345 wrote:
    ... I also tested 533M vs. 667M RAM. The slowdown for using 533M is 2% for one core utilized and 4% for both cores utilized. More significant than dual channel mode.

    Peter




    Hmmmm, is that condition similar to me??

    Would I be better to just remove the 2 512MB at 400 speed, reduce down from 3GB total to 2GB so that the 2GB could then run at 533??

    I've heard that the 533's wud be limited to 400 if the 400's are still in there!

    Or in other words do I really need the amt between 2GB - 3GB anyway???

    Whatchu think??
  • Personally, I chose 3G over 2G even though it meant a loss of peak performance of 2 to 4%, because the loss of performance when not having enough RAM is huge. So, if you really know you will never need more than 2G, you can go with the higher speed. More RAM means bigger disc caches and more programs you can run at one time. It is really up to you.

    Peter
  • Thank You PETER

    Hmmm my Task Manager shows 79 Processes and the CPU usage goes anywhere between 0 - 100%
    I don't know what commit Charge is but it shows 667M / 4449M

    With these characteristics do you think it best to keep the 3GB??

    Roger
  •  

    musiclover28463 wrote:
    Hmmm my Task Manager shows 79 Processes and the CPU usage goes anywhere between 0 - 100%
    I

    Wow that's a lot of processes running.  Since I'm not on my home computer now I can't say exactly how many I have running but I believe it to be around 45.  I would think having so many things running would cause your system to slow down.
     

     
  • Yep, I agree russell. MANY PROCESSES. That's y I wanted to put in more memory.

    I trimmed stuff outta the START-UP but don't know which ones to do an End Process on?

    Musicmatch won't load sometimes, when I go into Task Manager I see various musicmatch elements appear to b running in the processes so I END ALL OF THOSE. Then retry Musicmatch which then works :)

    roger
  • Guys. I've been following the direction this thread has taken but if I may I'd like to raise a further question on the original issue. First, my thanks to Peter345 for finding the official explanation. I knew it must be there somewhere.
     
    What I would really like to know is 'how do you tell if two Ram modules are matched?' I was careful to remove the original Dell parts which read "UL lead free 1GB 2RXB PC2 5300U 555 12 E0 1GB DDR2 667 CL5" so that I knew exactly what to add. I bought two modules by ATA (whoever they are!) and the labels both read: "PC2 5300 DDR SDRAM 128Mx64 1GB".
     
    Neither runs in my 9200 either on its own, together or together with either or both of the original modules.
     
    Why not?
    Mick
  • Sounds like the RAM is simply not compatible with the 9200 or is bad (not likely if you have multiple sticks that do the same thing).

    This is not an issue of matching. If the RAM is inserted by itself, it does not need to match anything. Matching is only needed to get dual channel mode.

    There are issues of "ranks" and "banks". I can't honestly say that I fully understand the definitions of these terms. 1G stick can have different numbers of ranks and banks. Some of those 1G sticks might work with your 9200 and others may not.


    Peter

    Message Edited by PETER345 on 04-30-2007 08:50 AM
  • Mmmm!
    So if you can't rely on what the label tells you to be certain it's compatible, how can you ever know what to get? I suppose I'm really asking "what is it that is different between these modules?"
     
     I would add this:
     
    1. I went to the Crucial site as suggested, input my specific details and it said the best match was the 4300s, which are slower that the 5300s that came with it (and if I understand it, would slow down all four modules if used together).
     
    2. The actual chips on the two modules are visually different, The new ones are the usual 2 blocks of four full-width chips whereas the OEM stuff has eight much smaller chips - I've not seen them this small before. Does that reveal anything?
     
    Mick
  • Sometimes memory is just not compatible. That is why so many people recommend crucial.com (which has very good prices these days) because of the guarantee compatibility. You can also buy from Dell.

    I don't know how you figure it out. Nobody seems to provide specs that allow you to determine what will work.

    For what it's worth, I bought some random cheap RAM for my 9100, 9200 and I6400. They all worked fine. In the past, I have had troubles with some machine (intel 810e boards) getting RAM to work. I always buy from a place that will take them back.

    The size and number of chips is not important (as far as I know). What can be important are the number of ranks (or banks). The number of ranks (banks) is equal to the total number of bits of the DRAM chips divided by 64. So 1 rank has exactly 64-bits of data from the DRAMs. If there are 128-bits (regardless of whether there are 4, 8 or 16 chips), then there are two ranks.

    Peter