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please help....about dual channel memory...

Discussion in 'Processors and Motherboards' started by RobinHood, Nov 5, 2006.

  1. Tmagic650 TS Ambassador Posts: 18,771   +62

    Thanks for the final correct info Sharkfood. I wasn't confused, but many others were. RobinHood, have you ever wondered why some memory is sold in matched pairs? They are needed for dual-channel operation...
  2. KingCody TechSpot Guru Posts: 1,568   +7

    to clarify the "conflicting information" here...

    In most cases, you must run an even number of matched RAM sticks (2 or 4) for dual channel, but on certain motherboards, it is indeed possible to run memory in dual-channel with 3 RAM sticks. see here for more info.
    I had only heard of Intel boards supporting it, but according to Superinc's post, his AMD-based Abit NF-7 (if he is referring to the system in his signature) also supported it as well. whether it supports it or not is motherboard/memory controller specific.

    RobinHood, read your motherboard manual to see if it supports dual channel in odd numbered configurations, and if so, what slots they need to be in. if you don't have the manual then you can download it from Gigabyte's website.

    :wave:
  3. Tmagic650 TS Ambassador Posts: 18,771   +62

    So if in the case above Channel A's total is 2GB, Channel B would have to be a single 2GB stick?
  4. Sharkfood TechSpot Guru Posts: 1,192

    That is basically the "DualDDR" configuration, which isn't quite the same as Dual-Channel, albeit you will have two channels, one for read, one for write but with limits on many operations. (i.e. not truly "dual-channel").

    DualDDR is more popular (and supported) on AMD systems as they allow two banks that add-up to the third bank. This was commonplace as many only shipped with 3-DIMM slots. You could, in essence, add two(2) 512mbs, then a single 1gig to achieve the distinct channels.

    In the case of the 90% though, you wont find bios or memory controller support on generic mainboards with any of this. Dual-channel on most 3rd party motherboards (and BIOS's) is limited solely to memory pairs for full-utilization and two channel memory operation.
  5. Tmagic650 TS Ambassador Posts: 18,771   +62

    I have only seen Intel Desktop Boards with Dual Channel bios and Dual Channel capability. I suppose other hi-end manufacturers have dual channel boards too
  6. Superinc Newcomer, in training Posts: 106

    it doesnt mean that its right ... lol . I still only running 1(512) gig..

    if your motherboard supports dual channel , use the 1 gig kit .. if it doesnt use all 3 sticks 1.5gigs .