Dell PowerEdge T620 Technical Guide - Page 21

Table 9 lists the DIMMs supported by the T620. For the latest information on supported memory, visit Dell.com. Capacity (GB) 2 2 2 4 4 4 4 4 8 8 16 16 32 32 Speed (MT/s) 1333 1600 1600 1333 1333 1600 1333 1600 1333 1600 1333 1600 1333 1333 Type Ranks per Data DIMM width RDIMM 1 x8 UDIMM 1 x8 RDIMM 1 X8 RDIMM 2 x8 RDIMM 1 x4 UDIMM 2 x8 UDIMM 2 x8 RDIMM 2 x8 RDIMM 2 x4 RDIMM 2 x4 RDIMM 2 x4 RDIMM 2 x4 LRDIMM 4 x4 RDIMM 4 x4 SDDC support Voltage Advanced ECC 1.35 Advanced ECC 1.35 Advanced ECC 1.35 Advanced ECC 1.35 All modes 1.35 Advanced ECC 1.35 Advanced ECC 1.35 Advanced ECC 1.35 All modes 1.35 All modes 1.35 All modes 1.35 All modes 1.35 All modes 1.35 All modes 1.35 Flexible memory configurations are supported on the T620, ranging from capacities of 2GB (minimum) to 768GB (maximum). The system supports up to 12 DIMMs per processor (up to 24 DIMMs in a dual-processor configuration). The T620 has 4 memory channels per processor, with each channel supporting up to 3 DIMMs. The T620 supports a flexible memory configuration, according to these basic rules:  Speed: If DIMMs of different speeds are mixed, all channels across all processors operate at the slowest DIMM's common frequency.  DIMM type: Only one type of DIMM is allowed per system: UDIMM, RDIMM, or LRDIMM. These types cannot be mixed. The following additional memory population guidelines apply to the T620:  Up to two quad-rank (QR) DIMMs and up to three dual-rank (DR) or single-rank (SR) DIMMs may be populated per channel. Although an LRDIMM is physically a QR DIMM, logic on the LRDIMM can make it appear as a DR DIMM to the system, allowing up to three LDRIMMs per channel.  DIMMs must be installed in each channel, starting with the DIMM farthest from the processor.  DIMMs should be installed with largest rank count to smallest. For example, if DR DIMMS are mixed with SR DIMMs, DR DIMMS should be placed in the lowest DIMM slots, followed by the SR DIMMs.