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:
• LR DIMMs, and RDIMMs must not be mixed.
• x4 and x8 DRAM based DIMMs can be mixed. For more information, see Mode-specific guidelines.
• A maximum of three single- 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 Mode-specific guidelines.
Table 2. 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
135 W (four cores, six
cores, or eight cores)
or 145 W
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
135 W (four cores, six
cores, or eight cores)
or 145 W
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)
NOTE: When using an 86 mm wide heat sink for dual processors, the memory module sockets
A10, A12, B10, and B12 are not available for population.
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