General memory module installation guidelines
Your system supports Flexible Memory Configuration, enabling the system to be configured and run in any valid chipset architectural
configuration. The following are the recommended guidelines for best performance:
•
LRDIMMs, and RDIMMs must not be mixed.
•
x4 and x8 DRAM based DIMMs can be mixed. For more information, see the Mode-specific guidelines section.
•
A maximum of three single-rank or dual-rank RDIMMs can be populated in a channel.
•
Populate DIMM sockets only if a processor is installed. For single-processor systems, sockets A1 to A12 are available. For dual-
processor systems, sockets A1 to A12 and sockets B1 to B12 are available.
•
Populate all sockets with white release tabs first, black, and then green.
•
Populate the sockets by highest capacity DIMM in the following order - first in sockets with white release levers and then black. For
example, if you want to mix 16 GB and 8 GB DIMMs, populate 16 GB DIMMs in the sockets with white release tabs and 8 GB DIMMs in
the sockets with black release tabs.
•
In a dual-processor configuration, the memory configuration for each processor must be identical. For example, if you populate socket
A1 for processor 1, then populate socket B1 for processor 2, and so on.
•
Memory modules of different sizes can be mixed provided that other memory population rules are followed (for example, 4 GB and 8
GB memory modules can be mixed).
•
Depending on mode-specific guidelines, populate four DIMMs per processor (one DIMM per channel) at a time to maximize
performance. For more information, see the Mode-specific guidelines section.
Table 23. Heat sink — processor configurations
Processor
Configuration
Processor Type (in Watts) Heat
Sink
Width
Number of DIMMs
Maximum System Capacity
Reliability, Availability, and
Serviceability (RAS) Features
Single processor
105 W, 120 W or 135 W
68 mm
12
12
Single processor
135 W (four cores, six cores,
or eight cores), 145 W, or 105
W (for acoustic configuration)
86 mm
10 (Three DIMMs in channel 0
and channel 2 and two DIMMs
in channel 1 and channel 3)
8 (Two DIMMs per channel)
NOTE:
When using an 86 mm wide heat sink for a single processor, the memory module sockets A10 and A12 are not
available for population.
Dual processor
105 W, 120 W or 135 W
68 mm
24
24
Dual processor
135 W (four cores, six cores,
or eight cores), 145 W, or 105
W (for acoustic configuration)
86 mm
20 (Three DIMMs in channel 0
and channel 2 and two DIMMs
in channel 1 and channel 3)
16 (Two DIMMs per channel)
Related References
Mode-specific guidelines
Four memory channels are allocated to each processor. The allowable configurations depend on the memory mode selected.
Advanced Error Correction Code
Advanced Error Correction Code (ECC) mode extends SDDC from x4 DRAM based DIMMs to both x4 and x8 DRAMs. This protects
against single DRAM chip failures during normal operation.
The installation guidelines for memory modules are as follows:
•
Memory modules must be identical in size, speed, and technology.
•
DIMMs installed in memory sockets with white release levers must be identical and the same rule applies for sockets with black release
levers. This ensures that identical DIMMs are installed in matched pair —for example, A1 with A2, A3 with A4, A5 with A6, and so on.
Installing and removing server module components
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