Lenovo 5468 Setup Manual page 49

• When you install or remove DIMMs, the node configuration information changes. When you restart the
node, the system displays a message that indicates that the memory configuration has changed. You can
use the Setup utility to view the node configuration information, see ThinkSystem SD650 Dual Node DWC
Tray and NeXtScale n1200 DWC Enclosure Setup Guide for more information.
• Install higher capacity (ranked) DIMMs first, following the population sequence for the memory mode
being used.
• The tray supports only industry-standard double-data-rate 4 (DDR4), 2666 MT/s, PC4-21300 (single-rank
or dual-rank), unbuffered or synchronous dynamic random-access memory (SDRAM) dual inline memory
modules (DIMMs) with error correcting code (ECC).
• Do not mix RDIMMs and LRDIMMs in the same node.
• The maximum operating speed of the node is determined by the slowest DIMM in the node.
• If you install a pair of DIMMs in DIMM connectors 1 and 3, the size and speed of the DIMMs that you
install in DIMM connectors 1 and 3 must match each other. However, they do not have to be the same
size and speed as the DIMMs that are installed in DIMM connectors 2 and 4.
• You can use compatible DIMMs from various manufacturers in the same pair.
• The specifications of a DDR4 DIMM are on a label on the DIMM, in the following format.
• gggGBpheRxff PC4-wwwwaa-mccd-bb
where:
– gggGB is the total capacity, in gigabytes, for primary bus (ECC not counted) 4GB, 8GB, 16GB, etc. (no
space between digits and units)
– pheR is the number of package ranks of memory installed and number of logical ranks per package
rank
– p =
• 1 = 1 package rank of SDRAMs installed
• 2 = 2 package ranks of SDRAMs installed
• 3 = 3 package ranks of SDRAMs installed
• 4 = 4 package ranks of SDRAMs installed
– he = blank for monolithic DRAMs, else for modules using stacked DRAM:
• h = DRAM package type
– D = multi-load DRAM stacking (DDP)
– Q = multi-load DRAM stacking (QDP)
– S = single load DRAM stacking (3DS)
• e = blank for SDP, DDP and QDP, else modules using 3DS stacks, logical ranks per package rank
– 2 = 2 logical ranks in each package rank
– 4 = 4 logical ranks in each package rank
– 8 = 8 logical ranks in each package rank
– R = rank(s)
– xff = Device organization (data bit width) of SDRAMs used on this assembly
• x4 = x4 organization (4 DQ lines per SDRAM)
• x8 = x8 organization
• x16 = x16 organization
– wwwww is the DIMM bandwidth, in MBps: 2133, 2400, 2666, 2933, 3200
.
Chapter 3 Solution hardware setup
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