Dell PowerEdge M820 Technical Manual page 19

Memory speeds of 1600MT/s, 1333MT/s, 1066MT/s, and 800MT/s are supported on the M820,
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 system runs at the highest speed for the
channel with the lowest DIMM voltage and speed. The operating speed of the memory is also
determined by the maximum speed supported by the processor, the speed settings in the BIOS, and
the operating voltage of the system.
Table 8 lists the memory configuration and performance details for the M820, based on the
population of the number and type of DIMMs per memory channel.
DIMM
DIMM 0
type
SR
DR
QR
SR
SR
DR
RDIMM
QR
QR
QR
SR
SR
SR
DR
QR
QR
QR
PowerEdge M820 Technical Guide
19
Number
DIMM 1 DIMM 2
DIMMs
SR
DR
DR
SR
DR
QR
SR SR
SR DR
DR DR
DR DR
QR
QR QR
Speed (MT/s)
of
800 1066
1 ∞ ∞
1 ∞ ∞
1 ∞ ∞
2 ∞ ∞
2 ∞ ∞
2 ∞ ∞
2 ∞
2 ∞
2 ∞
3 ∞ ∞
3 ∞ ∞
3 ∞ ∞
3 ∞ ∞
1 ∞
2 ∞
3 ∞
1333 1600
∞ ∞
∞ ∞
∞ ∞
∞
∞ ∞
∞
∞