Dell manual Quick Reference R810, R910, and M910 Memory Guide, Overview Intel Architecture

PowerEdge 11th Generation Servers: R810, R910, and M910 Memory Guidance

Sparing (DIMM and Rank): The system allocates a Rank or DIMM per channel as a Spare memory region, and is able to move a Rank or DIMM exhibiting correctable errors to the Spare while the operating system is running.

RDIMM: Registered DIMMs. Address, Control, and Clock lines are buffered and re-driven on the DIMM.

Overview Intel Architecture

PowerEdge 11Th Generation 4-socket servers use the new Intel Xeon 7500 and 6500 series processors that support DDR3 memory technology. Each processor has two memory controllers that support two Millbrook Memory Buffers. Every Millbrook Memory Buffer supports up to four DIMMs, which allows for greater scalability and memory performance.

It is important to recognize that memory speed and the processor chosen have interdependencies. The processor’s maximum QuickPath Interconnect (QPI) speed will determine the memory performance (1066 MTS, 978 MTS, or 800 MTs). Memory speed remains locked regardless of DIMM population. There is no speed change when populating increasing numbers of DIMMs. However, there are recommended population practices when upgrading or changing memory. DIMMs always must be populated identically in pairs (A1-A2, for example).

Table 1.	Quick Reference R810, R910, and M910 Memory Guide
DIMM Feature		Combine	Rules
Mixed Ranks		Yes	DIMMs of different Ranks can be mixed. The first slot of each
			channel populated (first two white tab DIMM slots on each memory
			buffer: A1, A2, A3, and A4) must be populated with the highest
			ranked DIMM.
Mixed Capacity		Yes	DIMMs must match (capacity, rank) across channels. For example, a
			1 GB RDIMM in A1 and A2 implies that A3 and A4 would need to be 1
			GB RDIMMs also. DIMM slots A5, A6, A7, and A8 could be a different
			capacity and rank.
Mixed Speeds		Yes	Nehalem EX Architecture will support a maximum memory speed of
			1066 MTs.
Mixed Vendors		Yes	Any Dell-sourced DDR3 DIMMs are supported, regardless of vendor or
			vendor mix. Where possible, Dell recommends using the same DIMM
			manufacturer.

Note: Only RDIMMS are supported with Intel 7500 and 6500 series processors.

Table 2.	Quick Comparison Intel Xeon 5500-5600 Series to Intel Xeon 7500-6500
Feature		Intel Xeon 5500-5600 Series	Intel Xeon 7500-6500 Series
DIMM Type		DDR3 (UDIMM or RDIMM)	DDR3 (RDIMM only)
DIMM Rank		DR, SR, or QR	DR, SR, or QR
All Memory channels operate at		Yes	Yes
the same frequency
Memory controllers per socket		1	2
Memory Channels per socket		3	4/8
			(4 SMI Buses/8 DDR3 Channels)
Maximum DIMMs per channel		3	2
DIMM Speed		1333 MTs (1 and 2 DPC)	1066 MTs (1 or 2 DPC)
(Speed shown is for top		1066 MTs (2 DPC)	(Same speed for SR, DR, or QR
bin…may be slower for down-		800 MTs (3 DPC)	DIMMs)

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