Dell PowerEdge XR8720t Installation and Service Manual

System memory guidelines

The PowerEdge XR8720t system supports DDR5 registered DIMMs (RDIMMs). System memory holds the instructions that are started by the processor.

Memory channels are organized as follows:

Table 1. Memory channelsThe table describes memory channels and how the channels are organized.
Processor	Channel A	Channel B	Channel C	Channel D	Channel E	Channel F	Channel G	Channel H
HCC Processor	Slot A5	Slot A7	Slot A6	Slot A8	N/A	N/A	N/A	N/A
XCC Processor*	Slot A1	Slot A3	Slot A5	Slot A7	Slot A2	Slot A4	Slot A6	Slot A8

Table 2. Supported memory matrixThe table describes supported memory matrix.
DIMM type	Rank	Capacity	DIMM rated voltage and speed	Operating Speed
DIMM type	Rank	Capacity	DIMM rated voltage and speed	1 DIMM per channel (DPC)
RDIMM	1 R	16 GB	DDR5 (1.1 V), 6400 MT/s	6400 MT/s
RDIMM	2 R	32 GB, 64 GB, 96 GB	DDR5 (1.1 V), 6400 MT/s	6400

NOTE:The processor may reduce the performance of the rated DIMM speed.

NOTE:HCC processors have a maximum support of 4 DIMMS per processor.

NOTE:Only XCC* processors support 8 DIMMS.

NOTE:Maximum DIMM transfer speed support dependent on CPU SKU and DIMM population.

NOTE:*Feature not available at initial product launch. Refer to the product configurator page on Dell.com to confirm feature availability.