DIMM Type DIMMs Populated/Channel Operating Frequency (inMT/s) Maximum DIMM Rank/Channel1.2 VRDIMM1 2133, 1866, 1600, and 1333 Single rank or dual rank2 2133, 1866, 1600, and 1333 Single rank or dual rank3 1866, 1600, and 1333 Single rank or dual rankLRDIMM1 2133, 1866, 1600, and 1333 Quad rank2 2133, 1866, 1600, and 1333 Quad rank3 1866, 1600, and 1333 Quad rankGeneral memory module installation guidelinesYour system supports Flexible Memory Configuration, enabling the system to be configured and run inany valid chipset architectural configuration. The following are the recommended guidelines for installingmemory modules:• RDIMMs and LRDIMMs must not be mixed.• x4 and x8 DRAM based memory modules can be mixed. For more information, see Mode-specificguidelines.• Up to three dual- or single-rank RDIMMs can be populated per channel.• Up to three LRDIMMs can be populated per channel regardless of rank count.• Populate memory module 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 B12are available.• Populate all sockets with white release tabs first, then black, and then green.• Populate the sockets by highest rank count in the following order — first in sockets with white releaselevers, then black, and then green. For example, if you want to mix single-rank and dual-rank memorymodules, populate dual-rank memory modules in the sockets with white release tabs and single-rankmemory modules in the sockets with black release tabs.• When mixing memory modules with different capacities, populate the sockets with memory moduleswith highest capacity first. For example, if you want to mix 4 GB and 8 GB memory modules, populate8 GB memory modules in the sockets with white release tabs and 4 GB memory modules in thesockets with black release tabs.• In a dual-processor configuration, the memory configuration for each processor should be identical.For example, if you populate socket A1 for processor 1, then populate socket B1 for processor 2, andso on.• Memory modules of different capacities can be mixed provided other memory population rules arefollowed (for example, 4 GB and 8 GB memory modules can be mixed).• Mixing of more than two memory module capacities in a system is not supported.• Populate four memory modules per processor (one DIMM per channel) at a time to maximizeperformance.Mode-specific guidelinesFour memory channels are allocated to each processor. The allowable configurations depend on thememory mode selected.61
