Unbuffered DIMMs (UDIMMs)
The following notes provide information that you must consider when you install UDIMMs.
- The memory channels run at the lowest common frequency of the DIMMs installed.
- The UDIMM options that are available for the server are 1 GB, 2 GB, 4 GB, and 8 GB (when available) DIMMs.
- The server supports up to two single-rank or dual-rank UDIMMs per channel.
- The following table lists the supported UDIMM population.
Table 1. Supported UDIMM population per channel DIMM connectors per channel DIMMs installed in each channel DIMM type DIMM speed Ranks per DIMM (any combination) 2 1 Unbuffered DDR3 ECC 1066, 1333, 1600 Single-rank, dual-rank 2 2 Unbuffered DDR3 ECC 1066, 1333, 1600 Single-rank, dual-rank
- The following table lists the maximum DIMM population using ranked UDIMMs.
Table 2. Maximum memory population using ranked UDIMMs (depending on your model) Number of UDIMMs DIMM type Size Total memory 4 Single-rank UDIMMs 1 GB 4 GB 4 Dual-rank UDIMMs 2 GB 8 GB 4 Dual-rank UDIMMs 4 GB 16 GB 4 Dual-rank UDIMMs 8 GB 32 GB
- The following table shows the UDIMM memory population rule to optimize the system performance.
Table 3. UDIMM population rule DIMM connector 1 DIMM connector 2 DIMM connector 3 DIMM connector 4 Populated Empty Empty Empty Populated Empty Populated Empty Populated Populated Populated Populated