Supported Memory - Dell PowerEdge R820 Technical Manual

The R820 supports the DIMMs listed in Table 9. For the latest information on supported memory,
visit Dell.com.
Capacity
(GB)
2
2
2
4
4
4
4
8
8
16
16
16
32
32
Flexible memory configurations are supported on the R820, ranging from capacities of 2 GB to
1.5 TB. The system supports up to 12 DIMMs per processor (up to 48 DIMMs in a four-processor
configuration). The R820 has four memory channels per processor, with each channel supporting
up to three DIMMs.
The R820 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, and LRDIMM cannot
be mixed.
The following additional memory population guidelines apply to the R820:

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.
For more information on memory configuration, see the
Manual
on Support.Dell.com/Manuals.
18 PowerEdge R820 Technical Guide
Speed Type Ranks per
(MT/s) DIMM
1333 RDIMM
1333 UDIMM
1600 RDIMM
1333 RDIMM
1333 RDIMM
1333 UDIMM
1600 RDIMM
1333 RDIMM
1600 RDIMM
1066 RDIMM
1333 RDIMM
1600 RDIMM
1333 LRDIMM
1333 RDIMM
Data SDDC support
width
1 x8 Advanced ECC
1 x8 Advanced ECC
1 x8 Advanced ECC
2 x8 Advanced ECC
1 x4 All modes
2 x8 Advanced ECC
2 x8 Advanced ECC
2 x4 All modes
2 x4 All modes
4 x4 All modes
2 x4 All modes
2 x4 All modes
4 x4 All modes
4 x4 All modes
Dell PowerEdge R820 Systems Owner's
Voltage
1.35
1.35
1.5
1.35
1.35
1.35
1.5
1.35
1.5
1.35
1.35
1.5
1.35
1.35