Triple-channel question

JestMe

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Jun 2, 2010
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Regarding triple-channel architecture, I know that you should have the same DIMMs across the channels... what I'm wondering is if it's OK to have different size DIMMs within the channels or should they all be the same?

IOW
Config A
CH1 - 1x8GB + 1x8GB - 16GB Total
CH2 - 1x8GB + 1x8GB - 16GB Total
CH3 - 1x8GB + 1x8GB - 16GB Total

versus
Config B
CH1 - 2x4GB + 1x8GB - 16GB Total
CH2 - 2x4GB + 1x8GB - 16GB Total
CH3 - 2x4GB + 1x8GB - 16GB Total

If config A is to be preferred, would it make much of a real difference?

I mean this question generically, though I needed to select a sub-category.

Thanks

ChrisM
 
Solution
Ok.

The 1st problem that I can see is that u want install 8GB module in one slot. Do u check if ur mobo support that 8GB in a single module?

Now, tri-channel and dual channel only works with stick of the same amount of RAM. If u bear in mind that, in both configurations A and B u get tri-channel the only difference is that in the Config B u get a tri-channel with 3x4GB plus another tri-channel with 3x8GB

JestMe

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Jun 2, 2010
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Probably a pretty newbie type question, I appreciate your response and apologize for not being clear enough, let me try again.

Assume that all RAM characteristics are the same except for capacity [size].

Also there are 3 channels each having 2 slots [6 total memory slots].

I understand the channels should each have the same capacity of RAM - as in my example above - both config A and config B have the same amount of RAM in each channel.

In Config A each channel & slot has 8GB of RAM installed [16 GB total per channel]. However, in Config B each channel has 2 - 4GB and 1 - 8GB of RAM installed [also 16 GB per channel]. In both cases the total installed RAM per channel is 16GB but in config B there is a mix of 2 different capacity RAM modules within each channel.

IOW can you mix different capacity RAM within the same channel... perhaps even having...

Channel 1 - having 1 - 16GB RAM module
Channel 2 - having 2 - 8GB RAM Module
Channel 3 - having 2 - 4GB plus 1 8GB RAM module

Each channel has 16 GB of RAM though different capacity RAM modules are used in each channel.

Does that clarify my question?

Thanks
 
Ok.

The 1st problem that I can see is that u want install 8GB module in one slot. Do u check if ur mobo support that 8GB in a single module?

Now, tri-channel and dual channel only works with stick of the same amount of RAM. If u bear in mind that, in both configurations A and B u get tri-channel the only difference is that in the Config B u get a tri-channel with 3x4GB plus another tri-channel with 3x8GB
 
Solution






Within the same channel, DIMMS must be matched. Else - (if it works at all) - it will run in single channel mode only.
 

JestMe

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Jun 2, 2010
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Thanks for the responses... I appreciate it.

So if I understand correctly then... each SLOT should use the same sticks..

What I am really trying to do is get 120GB on to a dual-processor with triple-channel architecture.

Each processor has 3 channels and each channel has 2 slots [total of 12 slots]. Therefore each channel would require 20 GB in order to total 120 GB.

To do that would require 1-16GB + 1-4GB stick per channel. If you cannot mix different sized sticks [16GB + 4GB] in the same channel then 120GB is not feasible.

It would further seem then that a total of 96GB [12-8GB] or 192GB [12-16GB] are both feasible, however any value in between 96 and 192 would not be feasible.

Thanks for your help.