Table 31. Memory populations and operating frequencies
DIMM Type
DIMMs
Populated/
Channel
Voltage
Operating
Frequency (in MT/s)
Maximum DIMM Rank/
Channel
RDIMM
1
1.2 V
2400, 2133, and 1866 Single rank or dual rank
2
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- or dual-rank RDIMMs can be populated in a channel.
• If memory modules with different speeds are installed, they operate at the speed of the slowest
installed memory module(s) or slower depending on system DIMM configuration.
• 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 32. 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
8
8
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
12
12
Related links
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