Lenovo ThinkSystem SR635 V3 - Memory Module Installation Rules and Order

Memory module installation rules and order
Memory modules must be installed in a specific order based on the memory configuration that you
implement and memory modules installed in the server.
Supported memory types
For information on the types of memory module supported by this server, see “Memory” section in
“Technical specifications” on page 3.
Information about optimizing memory performance and configuring memory is available at the Lenovo Press
website:
https://lenovopress.lenovo.com/servers/options/memory
In addition, you can take advantage of a memory configurator, which is available at the following site:
https://dcsc.lenovo.com/#/memory_configuration
Specific information about the required installation order of memory modules in your server based on the
system configuration and memory mode that you are implementing is shown below.
Memory module installation guideline
Follow the rules below when installing DIMMs:
• Mixing DIMMs from different vendors is supported in a system.
• Mixing x4 and x8 DIMMs is not allowed in a system.
• Mixing 3DS RDIMM and non-3DS RDIMM is not allowed in a system.
• Mixing 4-rank 3DS RDIMM and 8-rank 3DS RDIMM is not allowed in a system.
• Mixing EC4 and EC8 DIMMs is not allowed in a system.
• Only single-rank and dual-rank DIMM mixing is allowed in a system.
• When installing DIMMs with different capacity, install the DIMM with the highest capacity first following
population sequence.
• For best performance, the population recommends identical memory capacity and rank across all 12
channels.
Memory module installation order
Notes: In the following tables:
• S1-S12 indicate DIMM slots 1-12.
• 1-12 indicate the installation order.
The following table shows the DIMM population sequence.
Table 23. DIMM population sequence
Total DIMMs
Slot number
S12 S11 S10 S9 S8 S7 S6 S5 S4 S3 S2 S1
1 DIMM 1
2 DIMMs 1 2
4 DIMMs 3 1 2 4
Chapter 5. Hardware replacement procedures 49