Replacing Memory Dimms; Dimm Population Rules And Memory Performance Guidelines - Cisco UCS C220 M5 Maintaining

Maintaining the Server

Replacing Memory DIMMs

Caution DIMMs and their sockets are fragile and must be handled with care to avoid damage during installation.
Caution Cisco does not support third-party DIMMs. Using non-Cisco DIMMs in the server might result in system
problems or damage to the motherboard.
Note To ensure the best server performance, it is important that you are familiar with memory performance guidelines
and population rules before you install or replace DIMMs.

DIMM Population Rules and Memory Performance Guidelines

This topic describes the rules and guidelines for maximum memory performance.
DIMM Slot Numbering
The following figure shows the numbering of the DIMM slots on the motherboard.
Figure 21: DIMM Slot Numbering
DIMM Population Rules
Observe the following guidelines when installing or replacing DIMMs for maximum performance:
• Each CPU supports six memory channels.
• Each channel has two DIMM sockets (for example, channel A = slots A1, A2).
• In a single-CPU configuration, populate the channels for CPU1 only (A, B, C, D, E, F).
• For optimal performance, populate DIMMs in the order shown in the following table, depending on the
• CPU 1 supports channels A, B, C, D, E, F.
• CPU 2 supports channels G, H, J, K, L, M.
number of CPUs and the number of DIMMs per CPU. If your server has two CPUs, balance DIMMs
evenly across the two CPUs as shown in the table.
Replacing Memory DIMMs
Maintaining the Server
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