Dual channel operation on 3 memory slot board

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MGDMN

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I was looking at some of the Sager laptop configurations when I came across the NP8180 which supports dual channel but only comes with 3 memory slots. I cant seem to understand how this is possible. I contacted the support at XoticPC but I still dont understand. Here is the response that I received " How 3 dual channels will work is DIMM 1 can use DIMM 2 or 3 as its dual channel partners, DIMM 2 will use 3. Imagine 3 people holding hands standing in a circle, each person has someone elses hand in both hands. So they all have another stick to work with." With that answer in mind one thing that dont understand is where they stated that DIMM 1 can use DIMM 2 or DIMM 3 as a dual channel partner. What decides whether to use DIMM 1 with DIMM 2 or DIMM 1 with DIMM 3? Also, say DIMM 1 and DIMM 2 are being used in dual channel. How can DIMM 2 then also use DIMM 3 as a dual channel partner? There must be something that I am missing. I hope all that makes sense and someone can help me understand. Thanks for your time.
 
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Intel's Flex Memory Technology

However, it is: The capacity that can be matched is in dual-channel, while the remainder runs in single-channel.
 
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I think the guy from the manufacturer is feeding you bullshit. It's most likely that there are two slots on one channel and one slot on the other.

With current intel CPUs if you have a different amount of memory on each channel the memory both channels have in common operate in dual channel mode and the remaining memory operates in single channel mode.

So if you have 8GB one one channel and 4GB on the other you get 8GB of dual channel memory and 4GB of dual channel memory.
 
Thats what I thought but I was confused with the response that I received from their support tech. Thanks for the responses guys.
 
So if you have 8GB one one channel and 4GB on the other you get 8GB of dual channel memory and 4GB of dual channel memory.
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Would it not be 4GB dual channel and 8GB single channel?

"Dual-Channel Mode—Intel® Flex Memory Technology Mode
The IMC supports Intel Flex Memory Technology mode. This mode combines the
advantages of the Dual-Channel Symmetric (Interleaved) and Dual-Channel
Asymmetric Modes. Memory is divided into a symmetric and a asymmetric zone. The
symmetric zone starts at the lowest address in each channel and is contiguous until the
asymmetric zone begins or until the top address of the channel with the smaller
capacity is reached. In this mode, the system runs with one zone of dual-channel mode
and one zone of single-channel mode, simultaneously, across the whole memory array."
 
Ok, just so I am completely sure. If I decide to run three 4gb sticks, with 4gb in DIMM 1 and 4gb in DIMM 2, in dual channel, and the other 4gb stick in DIMM 3, does that mean that I will have 8gb in slots 1 and 2 in dual channel with the remaining 4gb stick staying in single channel?
 
Indeed, sorry for the typo.
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Oops, incorrect I am wrong and typed it up incorrect. 4GB on both channels equaling 8GB will be in dual channel mode. The left over 4GB will be in single channel with your example.

Ok, just so I am completely sure. If I decide to run three 4gb sticks, with 4gb in DIMM 1 and 4gb in DIMM 2, in dual channel, and the other 4gb stick in DIMM 3, does that mean that I will have 8gb in slots 1 and 2 in dual channel with the remaining 4gb stick staying in single channel?
Click to expand...

Exactly!
 
Alright, it is all making sense now. Thanks for the help guys.
 
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