CONFIGURATION GUIDE
–
NEC Express5800/A2040d, A2020d, A2010d, A1040d
NEC Corporation
Rev.2.0
– Oct. 2017
22
3.2 Memory Configuration
Please go to the appropriate section below in accordance with your memory configuration.
Memory configuration consists of 2 modes;
“Independent Mode” and “Lockstep Mode”.
Under each Mode, 2 features are available;
“Memory Rank Sparing” and “Memory Mirroring”.
Default setting at the server delivery is Lockstep Mode.
Independent Mode (only): Refer to
3.2.1
Lockstep Mode (only): Refer to
3.2.2
Memory Rank Sparing: Refer to
3.2.3
Memory Mirroring: Refer to
3.2.4
Please refer to “Memory” of “Reference” section for Memory on the Memory Riser Card (DIMM) installation
priority/order per Independent Mode, Lockstep Mode, Memory Rank Sparing and Memory Mirroring..
Memory Configuration Feature Comparison
See the table below for feature comparisons of memory configurations supported.
Independent Mode
(only)
Memory Rank Sparing
under Independent Mode
Memory Mirroring
under Independent Mode
Summary
In case of correctable
errors, switching to spare
memory rank
Redundant
memory
having the same data
Available Memory
-
1/2(8GB RDIMM),
1/2(16GB RDIMM)
3/4,1/2(32GB RDIMM)
of physical memory
1/2 of physical memory
Available Memory
Channel
1
4
4
4
Maximum Memory
Capacity
2
512GB(8GB RDIMM)
1024GB(16GB RDIMM)
2048GB(32GB RDIMM)
2048GB(32GB LRDIMM)
4096GB(64GB LRDIMM)
256GB(8GB RDIMM)
512GB(16GB RDIMM)
1536GB,1024GB
(32GB RDIMM)
256GB(8GB RDIMM)
512GB(16GB RDIMM)
1024GB(32GB RDIMM)
Data Correction
ECC, x4 SDDC
←
←
Notes
RDIMM and LRDIMM
cannot be mixed
Need to order memory for
sparing
Need to order memory for
mirroring
1
4 memory channels per Memory Riser Card.
2
All DIMMs have the same capacity
