Lenovo System x3250 M4, Installation And Service Manual

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– aa is the CAS latency, in clocks at maximum operating frequency
– bb is the JEDEC SPD Revision Encoding and Additions level
– cc is the reference design file for the design of the DIMM
– d is the revision number of the reference design of the DIMM
Note: To determine the type of a DIMM, see the label on the DIMM. The information on the label is in the
format xxxxx nRxxx PC3-xxxxx-xx-xx-xxx. The numeral in the sixth numerical position indicates whether
the DIMM is single-rank (n=1) or dual-rank (n=2).
Unbuffered DIMMs (UDIMMs)
The following notes provide information that you must consider when you install UDIMMs.
• The memory channels run at the lowest common frequency of the DIMMs installed.
• The UDIMM options that are available for the server are 1 GB, 2 GB, 4 GB, and 8 GB (when available)
DIMMs.
• The server supports up to two single-rank or dual-rank UDIMMs per channel.
• The following table lists the supported UDIMM population.
Table 4. Supported UDIMM population per channel
DIMM connectors
per channel DIMMs installed in
each channel
DIMM type DIMM speed
Ranks per DIMM
(any combination)
2 1 Unbuffered DDR3
ECC 1066, 1333, 1600 Single-rank,
dual-rank
2 2
Unbuffered DDR3
ECC
1066, 1333, 1600
Single-rank,
dual-rank
• The following table lists the maximum DIMM population using ranked UDIMMs.
Table 5. Maximum memory population using ranked UDIMMs (depending on your model)
Number of UDIMMs DIMM type Size Total memory
4
Single-rank UDIMMs 1 GB 4 GB
4 Dual-rank UDIMMs 2 GB 8 GB
4 Dual-rank UDIMMs 4 GB 16 GB
4 Dual-rank UDIMMs 8 GB 32 GB
• The following table shows the UDIMM memory population rule to optimize the system performance.
Table 6. UDIMM population rule
DIMM connector 1 DIMM connector 2 DIMM connector 3 DIMM connector 4
Populated Empty Empty Empty
Populated Empty Populated Empty
Populated Populated Populated Populated
Installing drives
This section describes the rules to install drives.
Chapter 2
.
Installing optional devices
27