25 PowerEdge R730 and R730xd Technical Guide
Table 9. DIMMs supported
Only
DIMM speed
The R730/R730xd support memory speeds of 2133MT/s, 1600MT/s, 1333MT/s, 1066MT/s and
800MT/s, depending on the DIMM types installed and the configuration. All memory on all
processors and channels run at the same speed and voltage. By default, the systems run at the
highest speed for the channel with the lowest DIMM voltage and speed. The operating speed of the
DIMM is also determined by the maximum speed supported by the processor, the speed settings in
the BIOS, and the operating voltage of the system. Not all processors support 2133MT/s memory
speed.
Table 10. Memory configuration and performance
DIMM rated voltage,
speed
Memory configurations
The R730/R730xd support flexible memory configurations ranging from capacities of 4GB to 768GB.
The system supports up to 12 DIMMs per processor (up to 24 DIMMs in a dual-processor
configuration). The R730/R730xd have four memory channels per processor, with each channel
supporting up to three DIMMs.
Both systems support a flexible memory configuration, according to these basic rules:
ï‚· Speed: If DIMMs of different speeds are mixed, all channels across all processors operate at the
slowest DIMM’s common frequency.
ï‚· DIMM type: Only one type of DIMM is allowed per system, either RDIMM or LRDIMM.
Memory population guidelines
The following memory population guidelines apply to the R730 and R730xd:
ï‚· Can mix DIMMs with x4 and x8 data widths
ï‚· Can mix DIMMs with different capacities
— Population rules require the largest capacity DIMM be placed first
— Maximum of two different capacity DIMMs allowed in a system
ï‚· Can mix DIMMs with different ranks; maximum of two different rank DIMMs allowed in a system