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Chapter 3: Maintenance and Component Installation
Memory Population Guidelines
•
All DIMMs must be DDR4.
•
Balance memory. Using unbalanced memory topology, such as populating two DIMMs in
one channel while populating one DIMM in another channel, reduces performance. It is
not recommended for Supermicro systems.
•
In dual-CPU configurations, memory must be installed in the slots associated with the
installed CPUs.
Guidelines Regarding Mixing DIMMs
•
Populating slots with a pair of DIMM modules of the same type and size results in inter-
leaved memory, which improves memory performance.
•
Use memory modules of the same type and speed, as mixing is not allowed.
•
x4 and x8 DIMMs can be mixed in the same channel.
•
Mixing of LRDIMMs and RDIMMs is not allowed in the same channel, across different
channels, and across different sockets.
•
Mixing of non-3DS and 3DS LRDIMM is not allowed in the same channel, across different
channels, and across different sockets.
DIMM Construction
•
RDIMM (
non-3DS
) Raw Cards: A/B (2Rx4), C (1Rx4), D (1Rx8), E (2Rx8)
•
3DS RDIMM Raw Cards: A/B (4Rx4)
•
LRDIMM (
non-3DS
) Raw Cards: D/E (4Rx4)
•
3DS LRDIMM Raw Cards: A/B (8Rx4)
Memory Population Sequence
Blue slots versus black slots:
Install the first DIMM in the blue memory slot, which is the
first of a memory channel. Then, if using two DIMMs per channel, install the second DIMM
in the black slot.
The following memory population sequence table was created based on guidelines provided
by Intel to support Supermicro motherboards. The diagram is for illustrative purposes; your
motherboard may look different.