Memory upgrade

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cyruspy

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Mar 26, 2016
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I have a somewhat dated home lab running dual E5-2670 on a S2600CP2J motherboard. Would like to jump to an 16x32GB memory configuration.

I'm looking at modules listed as PC3-14900R and PC3-14900L (somewhat cheaper). Any insights on which should I get?
 
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alex_stief

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May 31, 2016
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Why? Xeon E5-2670 maxes out at DDR3-1600. Buying faster memory is just a waste of money in my opinion.
 

Spartacus

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May 27, 2019
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Why? Xeon E5-2670 maxes out at DDR3-1600. Buying faster memory is just a waste of money in my opinion.
I second this, unless you're planning on upgrading to a v2, not much use going for 1866 and even then the increased cost is pretty negligible.
 

cyruspy

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I second this, unless you're planning on upgrading to a v2, not much use going for 1866 and even then the increased cost is pretty negligible.
I'll definetly jump to v2 when makes sense (when software like ESXi starts complaining about unsupported processors and v2 gets cheaper)
 

cyruspy

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Most probably, will buy whatever is most cost effective. Just wanted to check 12800L/14900L modules are as good as 12800R/14900R ones (right now I have 12800R modules)
 

MBastian

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Jul 17, 2016
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I have a somewhat date home lab running dual E5-2670 on a S2600CP2J motherboard. Would like to jump to an 16x32GB memory configuration.

I'm looking at modules listed as PC3-14900R and PC3-14900L (somewhat cheaper). Any insights on which should I get?
Can that board, even with v2 cpus, drive 16x 32GB modules (quad-rank only?) at more than 800 Mhz? I know there are systems/motherboard out there that can but they are very rare.
 
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cyruspy

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It's not that clear to me though if the modules listed as PC3-14900L are LRDIMM or if they are low voltage irrespective of whether they are RDIMM or LRDIMM
 

MBastian

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If I remember correctly PC3L-XXXXXR is for low voltage modules and PC3-XXXXXLR is for LRDIMMs.

Edit: Forgive me the question but honestly, do you really really need 0.5TB of RAM? It seems like spending alot of money in a dead end technology with a lot of potential problems. I'd suggest you consider upgrading to two E5-2680 v2 and 16x 16GB 12800R modules instead.
 
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cyruspy

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Seems the correct nomenclature is:

#RDIMM
PC3-12800R (1.5v)
PC3-14900L (1.35v)

#LRDIMM
PC3L-12800R (1.5v)
PC3L-14900L (1.35v)

Jumping to a dual E5-2697 v2 will require + us$ 600. E5-2680 v2 would be half of that (us$300), could be a second step to gain 8 cores and better power efficiency.

Right now I have to test a VCF4 deployment (vSphere+vSAN+NSX+vRA+vRO,vRLI+vRNI) with a couple of different combinations, that's why I need that memory capacity.
 
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cyruspy

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If I remember correctly PC3L-XXXXXR is for low voltage modules and PC3-XXXXXLR is for LRDIMMs.

Edit: Forgive me the question but honestly, do you really really need 0.5TB of RAM? It seems like spending alot of money in a dead end technology with a lot of potential problems. I'd suggest you consider upgrading to two E5-2680 v2 and 16x 16GB 12800R modules instead.
Just to clarify, I own the MB and dual E5-2670 server already (bought 3 years ago aprox). Those are not part of the purchase, I'm looking for a memory expansion.
 

Spartacus

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^ I agree, sort of, I think he's confusing the L and R postional nomenclature
The L at the end of PC3 (or lack there of) denotates whether its a normal or low voltage dimm ~ PC3 is 1.5v and PC3L is 1.35v regardless of the speed or dimm type.
The R or L at the end of the speed (12800 or 14900 in this case), denotates whether its registered dimm (RDIMM) or load reduced dimm (LRDIMM).
So since the board can take standard (1.5v) or low voltage (1.35v) modules, your chart should be:

#RDIMM
PC3-12800R (1.5v)
PC3-14900R (1.5v)
PC3L-12800R (1.35v)
PC3L-14900R (1.35v)

#LRDIMM
PC3-12800L (1.5v)
PC3-14900L (1.5v)
PC3L-12800L (1.35v)
PC3L-14900L (1.35v)


This is assuming you're replacing all the ram, there are certain restrictions around mixing and matching low voltage/regular, and LRDIMM and RDIMM.
 
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Markess

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May 19, 2018
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^ I agree, sort of, I think he's confusing the L and R postional nomenclature
The L at the end of PC3 (or lack there of) denotates whether its a normal or low voltage dimm ~ PC3 is 1.5v and PC3L is 1.35v regardless of the speed or dimm type.
The R or L at the end of the speed (12800 or 14900 in this case), denotates whether its registered dimm (RDIMM) or load reduced dimm (LRDIMM).
So since the board can take standard (1.5v) or low voltage (1.35v) modules, your chart should be:

#RDIMM
PC3-12800R (1.5v)
PC3-14900R (1.5v)
PC3L-12800R (1.35v)
PC3L-14900R (1.35v)

#LRDIMM
PC3-12800L (1.5v)
PC3-14900L (1.5v)
PC3L-12800L (1.35v)
PC3L-14900L (1.35v)


This is assuming you're replacing all the ram, there are certain restrictions around mixing and matching low voltage/regular, and LRDIMM and RDIMM.
Yes...this ^
 

cyruspy

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Mar 26, 2016
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^ I agree, sort of, I think he's confusing the L and R postional nomenclature
The L at the end of PC3 (or lack there of) denotates whether its a normal or low voltage dimm ~ PC3 is 1.5v and PC3L is 1.35v regardless of the speed or dimm type.
The R or L at the end of the speed (12800 or 14900 in this case), denotates whether its registered dimm (RDIMM) or load reduced dimm (LRDIMM).
So since the board can take standard (1.5v) or low voltage (1.35v) modules, your chart should be:

#RDIMM
PC3-12800R (1.5v)
PC3-14900R (1.5v)
PC3L-12800R (1.35v)
PC3L-14900R (1.35v)

#LRDIMM
PC3-12800L (1.5v)
PC3-14900L (1.5v)
PC3L-12800L (1.35v)
PC3L-14900L (1.35v)


This is assuming you're replacing all the ram, there are certain restrictions around mixing and matching low voltage/regular, and LRDIMM and RDIMM.
Thanks for clarifying!. Ebay listings are a salad of a combination of these (states something, SKU from picture says otherwise)
 
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