Can DL580-G5 and BL680-G5 access all memory with single or dual processors?

[chuckk281]

Stephen had a question regarding memory access on servers:

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Can anyone confirm that the DL580-G5 and BL680-G5 can access ALL 16 (or 32) memory DIMMs if only one or two CPUs are installed. Customer wants LOTS of memory but minimum CPU power (this also reduces Sybase per CORE application licence cost).

(With Nehalem, the DIMMs associated with a given processor socket are only accessible if a processor is installed in that socket, which halves the memory available on a 2S Nehalem server when only one CPU is installed).

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Eirik and Andrey responded:

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Eirik said: 

You would at least get latency to access the memory dimms on the side where the CPU's are installed.

It might be a better solution to install both CPU's but disable half of the cores on both ?

Andrey also answered: 

Yes, CU may fill all DIMM slots even with 1 CPU, In opposite to G7 (Xeon 7500),

G5 architecture (Xeon 7400)  have shared memory subsystem (shared by both socket via 7300 chipset)

http://ark.intel.com/Product.aspx?id=36947  (click Block Diagrams)

http://h20000.www2.hp.com/bc/docs/support/SupportManual/c01136096/c01136096.pdf

http://bizsupport2.austin.hp.com/bc/docs/support/SupportManual/c01062660/c01062660.pdf

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Hope this helps. Are you using single processor and all the DIMMs? Let us know your experiences.