HPE Cloudline CL2200 Gen10, Руководство пользователя и по обслуживанию

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Removal and replacement procedures 74
Memory options
The memory controller is integrated in the processor:

Supports DDR4 2666/2400/2133 MT/s RDIMM (up to 32GB) and LRDIMM (up to 64GB) memory
modules.

Support single-rank (SR), dual-rank (DR) and quad-rank (QR) DIMM modules.

Per processor:
[For RDIMM]: 384 GB maximum memory (12 x 32GB RDIMM)
[For LRDIMM]: 768 GB maximum memory (12 x 64GB LRDIMM)

2 DIMM per channel.
Single-, dual-, and quad-rank DIMMs
To understand and configure memory protection modes properly, an understanding of single-, dual-, and
quad-rank DIMMs is helpful. Some DIMM configuration requirements are based on these classifications.
A single-rank DIMM has one set of memory chips that is accessed while writing to or reading from the
memory. A dual-rank DIMM is similar to having two single-rank DIMMs on the same module, with only one
rank accessible at a time. A quad-rank DIMM is, effectively, two dual-rank DIMMs on the same module.
Only one rank is accessible at a time. The server memory control subsystem selects the proper rank
within the DIMM when writing to or reading from the DIMM.
Dual- and quad-rank DIMMs provide the greatest capacity with the existing memory technology. For
example, if current DRAM technology supports 8-GB single-rank DIMMs, a dual-rank DIMM would be 16
GB, and a quad-rank DIMM would be 32 GB.
LRDIMMs are labeled as quad-rank DIMMs. There are four ranks of DRAM on the DIMM, but the
LRDIMM buffer creates an abstraction that allows the DIMM to appear as a dual-rank DIMM to the
system. The LRDIMM buffer isolates the electrical loading of the DRAM from the system to allow for faster
operation. This allows higher memory operating speed compared to quad-rank RDIMMs.