User guide

Hardware options installation 27
• Observe the general DIMM slot population guidelines (on page 25).
• Always install DIMMs in channels 1 and 2 for each installed processor.
• Do not install DIMMs in channel 3 for any processor.
• DIMM configuration on channel 1 and channel 2 of a processor must be identical.
• In multi-processor configurations, each processor must have a valid Lockstep Memory configuration.
• In multi-processor configurations, each processor may have a different valid Lockstep Memory
configuration.
Single-processor Lockstep population order
For Lockstep memory mode configurations with a single processor, populate the DIMM slots in the following
order:
• RDIMM
o First: A and B
o Next: D and E
o Last: G and H
o Do not populate slots C, F, or I.
• UDIMM
o First: A and B
o Last: D and E
o Do not populate slots C, F, G, H, or I.
After installing the DIMMs, use RBSU to configure the system for Lockstep memory support ("Configuring
lockstep memory" on page 52).
Multi-processor Lockstep population order
For Lockstep memory mode configurations with multiple processors, populate the DIMM slots for each
processor in the following order:
• RDIMM
o First: A and B
o Next: D and E
o Last: G and H
o Do not populate slots C, F, or I.
• UDIMM
o First: A and B
o Last: D and E
o Do not populate slots C, F, G, H, or I.
After installing the DIMMs, use RBSU to configure the system for Lockstep memory support ("Configuring
lockstep memory" on page 52).
Installing DIMMs