Registered Dimms (Rdimms) - IBM System x3250 M3 Type 4251 Installation And User Manual

Registered DIMMs (RDIMMs)

The following notes provide information that you must consider when you install
RDIMMs:
v The memory channels run at the fastest common frequency of the installed
v RDIMMs are supported in models with an Intel Xeon 3400 series processor.
v Do not use both RDIMMs and UDIMMs in the same server.
v The server supports up to three single-rank, dual-rank, or quad-rank RDIMMs per
v The RDIMM options that are available for the server are 1 GB, 2 GB, 4 GB, and
v You can install a maximum of 32 GB of memory in the server when you use
v The following table lists the supported RDIMM population.
v The following table lists the maximum DIMM population using ranked RDIMMs.
v The following table shows the RDIMM memory population rule to optimize the
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IBM System x3250 M3 Types 4251, 4252, and 4261: Installation and User's Guide
DIMMs.
channel.
8 GB DIMMs.
RDIMMs.
Table 8. Supported RDIMM population per channel
DIMM
connectors per DIMMs installed
channel in each channel DIMM type
3 1
3 2
3 3
3 1
3 2
Table 9. Maximum memory population using ranked RDIMMs (depending on your model)
Number of RDIMMs DIMM type
6 Single-rank RDIMMs
6 Dual-rank RDIMMs
4 Dual-rank RDIMMs
4 Quad-rank RDIMMs
6 Dual-rank RDIMMs
4 Quad-rank RDIMMs
system performance.
Table 10. RDIMM population rule for dual-channel symmetric mode
DIMM DIMM
connector 1 connector 2
Populated Empty
Populated Empty
DIMM speed
Registered 1066, 1333
DDR3 ECC
Registered 1066, 1333
DDR3 ECC
Registered 800
DDR3 ECC
Registered 1066
DDR3 ECC
Registered 800
DDR3 ECC
Size
1 GB
2 GB
4 GB
4 GB
4 GB
8 GB
DIMM DIMM
connector 3 connector 4
Empty Empty
Empty Populated
Ranks per
DIMM (any
combination)
Single-rank,
dual-rank
Single-rank,
dual-rank
Single-rank,
dual-rank
Quad-rank
Quad-rank
Total memory
6 GB
12 GB
16 GB
16 GB
24 GB
32 GB
DIMM DIMM
connector 5 connector 6
Empty Empty
Empty Empty