3-21
Cisco UCS C24 Server Installation and Service Guide
OL-26647-01z
Chapter 3 Maintaining the Server
Installing or Replacing Server Components
Figure 3-12 DIMM Slots and CPUs
Observe the following guidelines when installing or replacing DIMMs:
• Each CPU supports three memory channels.
–
CPU1 supports channels A, B, and C.
–
CPU2 supports channels D, E, and F
Note In a single-CPU system, the maximum number of DIMMs is six (only the six slots supported
by CPU1).
• Each channel has two DIMM slots (for example, channel A = slots A0 and A1).
–
A channel can operate with one or two DIMMs installed.
–
If a channel has only one DIMM, populate slot 0 first (the blue slot).
• When both CPUs are installed, populate the DIMM slots of each CPU identically.
–
Fill blue slots in the channels first: A0, D0, B0, E0, C0, F0
–
Fill black slots in the channels second: A1, D1, B1, E1, C1, F1
• Any DIMM installed in a DIMM socket for which the CPU is absent is not recognized. In a
single-CPU configuration, populate the channels for CPU1 only.
285209
A0
A1
B0
B1
C0
C1
D0
D1
E0
E1
F0
F1
Front of Server
CPU1
CPU2