Specifications

19 PowerEdge M820 Technical Guide
Memory speed
The M820 server supports memory speeds of 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 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.
Table 8. Memory speed capabilities
DIMM
type
DIMM 0
DIMM 1
DIMM 2
Number
of
DIMMs
Speed (MT/s)
800*
1066*
1333
1600
RDIMM
SR
1
∞
∞
∞
∞
DR
1
∞
∞
∞
∞
QR
1
∞
∞
∞
SR
SR
2
∞
∞
∞
∞
SR
DR
2
∞
∞
∞
∞
DR
DR
2
∞
∞
∞
∞
QR
SR
2
∞
∞
QR
DR
2
∞
∞
QR
QR
2
∞
∞
SR
SR
SR
3
∞
∞
∞
SR
SR
DR
3
∞
∞
∞
SR
DR
DR
3
∞
∞
∞
DR
DR
DR
3
∞
∞
∞
LRDIMM
QR
1
∞
∞
QR
QR
2
∞
∞
QR
QR
QR
3
∞
∞
*Although the M820 supports DIMM speeds of 800MT/s and 1066MT/s, you can only purchase this system with DIMM
speeds of 1333MT/s and 1600MT/s on Dell.com/PowerEdge.
Memory RAS features
Reliability, availability, and serviceability (RAS) features help keep the system online and operational
without significant impact to performance, and can decrease data loss and crashing due to errors.
RAS aids in rapid, accurate diagnosis of faults that require service. Table 9 describes the memory RAS
features supported on the M820.