How many slots to fill in ddr 3 ram

Status
Not open for further replies.

abhijeet_sharan

Distinguished
Jan 13, 2012
5
0
18,510
I want to install DDR 3 on my Dual Quad Core Xeon machine . Is it truev that i must utilize three slots or multiples thereof ? Utilizing 2 slots or multiples there of will make the system under perform or to be precise make the DDR 3 perform more like DDr 2 ?? Help appreciated .
 
Solution


Any dual quad core Xeon machine out right now that uses DDR3 uses 3-channel memory. Ideally you will populate memory in multiples of three, keeping the number of modules the same between both the CPUs. Having fewer than three modules per CPU can reduce performance as you are not fully utilizing the memory controller's available bandwidth. LGA1366 Xeons do down-clock all of the memory in the system once you reach a certain number of modules per CPU, but...
If your board supports triple channel ram, then you must add ram in sets of 3 otherwise your system will automatically downgrade to single channel speeds. If it supports dual channel, then you add sets in multiples of 2 to enable dual channel access. DDR3 will work in either application.
 
What do you mean by make the DDR3 perform more like DDR2? All modern DDR3 modules are faster than any DDR2 modules so the point seems moot. Also, you can only install DDR3 memory on a motherboard and CPU system that supports it. Your motherboard probably doesn't because I think there aren't any Xeon boards that support DDR2 and DDR3.

DDR3 and DDR2 are different generations of the DDR (Double Data Rate) technology. They are not compatible at all with each other, never have been, and never will be. A memory module is either DDR2 or DDR3 or a different memory tech but no modules support multiple technologies nor different generations of the same technology.

DDR3 memory modules have a different pin-out then DDR2 even though they have the same number of pins (240, 120 per side of DIMM). A few motherboards have some DDR2 and DDR3 slots but they are all old consumer motherboards.
 

abhijeet_sharan

Distinguished
Jan 13, 2012
5
0
18,510
Thank you all . Why i asked is as follows : A SuperMicro sales guy was offering to install 16 GB DDR 3 RAM in my new Xeon Dual Quad Core machine ( 4+4+4+4) . And insisted he was right even when i pointed out this to him .
My Mac Pro sales guy has also installed 16 GB DDR3 RAM ( 4+4+4+4) on my Dual Quad Core Mac Pro .
This is India . Or shall we say Incredible India !! After receiving your replies I have ordered the system Ram s to be installed in multiples of ( 4+4+4) om both mu Xeon and Mac Pros .
Thank you everybody . Very much !!
 


Any dual quad core Xeon machine out right now that uses DDR3 uses 3-channel memory. Ideally you will populate memory in multiples of three, keeping the number of modules the same between both the CPUs. Having fewer than three modules per CPU can reduce performance as you are not fully utilizing the memory controller's available bandwidth. LGA1366 Xeons do down-clock all of the memory in the system once you reach a certain number of modules per CPU, but that number varies a lot by which exact CPU you have and exactly how many modules you plan to put in it, as well as how many ranks each memory module has. You would need to post what exact CPUs you have and the number and exact model number of your RAM here for anybody to tell you exactly what would happen.
 
Solution

abhijeet_sharan

Distinguished
Jan 13, 2012
5
0
18,510
The configuration is as follows :
Processor : Dual Processors of Intel Xeon Quad Core E 5620/ 2.4o GHz/12MB L3 Cache /5.86 GT/s
Motherboard : Supermicro Intel 5520 , Tylersburg Chipset
RAM : For each processor 4+4+4 GB of DDR-3 1066MHz ECC Registered RAM ie for each processor we intend to install 3 DDR3 RAMS of 4 GB Each . Total RAM per Processor : 12GB . Therefore for 2 processors tota; RAM will be 24GB DDR 3 .

Is this configuration technically ok and will it work ?

Thank you very much .
 


That will work perfectly well.
 
Status
Not open for further replies.