Memory Population Rules - Cisco UCS C220 M3 User Manual

SUPPLEMENTAL MATERIAL

Memory Population Rules

When considering the memory configuration of your server, you should consider the following items:
For optimum performance, populate at least one DIMM per memory channel per CPU. If
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using 4 GB DIMMs, you must populate 2 DIMMs per CPU memory channel.
The server supports registered DIMMs (RDIMMs) or load-reduced DIMMS (LRDIMMs), however,
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do not mix RDIMMs and LRDIMMs in a server.
Each channel has two DIMM slots (for example, channel A = slots A1 and A2).
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When both CPUs are installed, populate the DIMM slots of each CPU identically.
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Any DIMM installed in a DIMM socket for which the CPU is absent is not recognized.
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Observe the DIMM mixing rules shown in
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Table 26
DIMM Parameter Mixed
DIMM Size (4, 8, 16 GB)
DIMM Speed
(1066, 1333, or 1600 MHz)
DIMM Type (R-DIMM)
Notes . . .
1. Only 1333 and 1600 MHz DIMMs are currently available for the C220 M3 server.
50 Cisco UCS Cisco UCS C220 M3 High-Density Rack Server (Small Form Factor Disk Drive Model)
A channel can operate with one or two DIMMs installed.
If a channel has only one DIMM, populate slot 1 first (the blue slot).
Fill blue slots in the channels first: A1, E1, B1, F1, C1, G1, D1, H1
Fill black slots in the channels second: A2, E2, B2, F2, C2, G2, D2, H2
DIMM Mixing Rules for C220 M3 Server
Mix Across a Single Bank?
No—Must be same size in the
same bank
No—Must be same speed in
the same bank.
1
No—All DIMMs in a bank must
be same type.
Table 26
Mix Across Multiple Banks?
Yes—Different banks can use
different DIMM sizes (as long
as all DIMMs in a single bank
use the same DIMM size).
No—All DIMMs in the server
must be same speed.
No—All DIMMs in the server
must be same type.