Hardware options installation 45
Multi-processor Advanced ECC population order
For Advanced ECC mode configurations with multiple processors, populate the DIMM slots for each
processor in the following order:
• RDIMM: Sequentially in alphabetical order (A through I)
• UDIMM: A through F, sequentially in alphabetical order. Do not populate DIMM slots G through I.
Lockstep Memory population guidelines
For Lockstep memory mode configurations, observe the following guidelines:
• Observe the general DIMM slot population guidelines (on page 44).
• 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 78).
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.
