Quad Ranked Memory in Motherboard? [SOLVED]

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invulnarable27

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Hello,

Both are 1 socket 1U servers, both use Intel CPU's.

1. Dell R310 Server: http://www.dell.com/us/business/p/poweredge-r310/pd (6 DIMM slots)

2. Dell R410 Server: http://www.dell.com/us/business/p/poweredge-r410/pd (8 DIMM slots)


For server #1 R310, the specs do not show compatibility with quad-ranked 16GB modules, unlike Server #2. Max supported is 32GB. Why is this? Can I still use quad-ranked 16GB modules?

I read some documentation about how servers/mobos can only address a certain number of ranks...is that the problem holding back Server #1 R310?


CPU's can address as many DIMM slots you present to them right? The only thing holding them back is the motherboard design? The max I've seen on Dell's website is that a sinlge CPU can address 16 DIMM slots of memory. Can it address more?


Thanks
 
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The total number of memory addresses is important. It is easier to address 16 RAM slots x 1gb each than 16 RAM slots with 8gb each.

Regardless if you have 1x 4GB, 2x 2GB, or 4x 1GB, or 8x 512k, or 16 x 256k the 32 bit versions of windows can only address 3.25GBs of RAM.

That is limited by the operating system. There is probably some limit with a 64 bit OS, but it is probably so much higher than 3.25 GBs of RAM that it might as well not be mentioned with current gen technology.

That being said, 16 x 8gb (108 GB RAM) might hit that figure.

In any event, there are multiple things that could be holding those servers back including both the motherboard and the operating system. It is conceivable that other bottlenecks may also exist...
The total number of memory addresses is important. It is easier to address 16 RAM slots x 1gb each than 16 RAM slots with 8gb each.

Regardless if you have 1x 4GB, 2x 2GB, or 4x 1GB, or 8x 512k, or 16 x 256k the 32 bit versions of windows can only address 3.25GBs of RAM.

That is limited by the operating system. There is probably some limit with a 64 bit OS, but it is probably so much higher than 3.25 GBs of RAM that it might as well not be mentioned with current gen technology.

That being said, 16 x 8gb (108 GB RAM) might hit that figure.

In any event, there are multiple things that could be holding those servers back including both the motherboard and the operating system. It is conceivable that other bottlenecks may also exist.

Whichever was the most restrictive would be the one that is operational.

If your motherboard says 2 GB max and windows xp says 3.25 GBs max, then the 2gb would be the one in effect, for example.
 
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invulnarable27

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Hello,

The OS is fine, Windows Server Enterprise. I was more interested if I could use quad-ranked 16GB modules on the R310.

Update just found my answer: http://www.ec.kingston.com/ecom/configurator_new/modelsinfo.asp?SysID=73492&mfr=Dell&model=PowerEdge+R310+%28Xeon+X3400+series%2C+Xeon+L3426%29&search_type=&root=us&LinkBack=http%3A%2F%2Fwww.kingston.com&Sys=73492-Dell-PowerEdge+R310+%28Xeon+X3400+series%2C+Xeon+L3426%29&distributor=0&submit1=Search

Looks like I can use quad-ranked, however it doesn't extend to 16GB. Probably they didn't test it yet.

I have never seen any documentation regarding a motherboard only able to support a certain number of ranks as below describes:

Ex: For example if a server can address 8 ranks. It may take a combination of 1GB, 2GB, 4GB and 16GB module to achieve this.
4 x 2GB Rank 2 modules = 8 Ranks and 8GB, or
8 X 2GB Rank 1 modules = 8 Ranks and 16GB or alternatively using 16GB modules,
2 X 16GB Rank 4 modules = 8 Ranks and 32GB

Thread completed.
 
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