User Manual
IBM System x3550 M4 17
Mixing 1.5 V and 1.35 V DIMMs in the same server is supported; in such cases, all DIMMs operate at
1.5 V.
The maximum number of ranks supported per one channel is eight (with the exception of Load
Reduced DIMMs, where more than eight ranks are supported because one quad-rank LRDIMM
provides the same electrical load on a memory bus as a single-rank RDIMM).
The maximum quantity of DIMMs that can be installed in server depends on number of CPUs, DIMM
type, rank, and operating voltage as shown in the "Maximum quantity" row in the following table.
All DIMMs in all CPU memory channels operate at the same speed, which is determined as the
lowest value of:
The memory speed supported by the specific CPU.
The lowest of maximum operating speeds for the selected memory configuration that depends on
rated speed, operating voltage, and quantity of DIMMs per channel, as shown under "Maximum
operating speed" section in the following table.
The following table (Parts 1, 2, and 3) shows the characteristics of the supported DIMMs. Tables cells
highlighted with a gray background indicate when the combination of DIMM voltage and the number of
DIMMs per channel still allows the DIMMs to operate at a rated speed.
Table 5. Maximum memory speeds (Part 1: Intel Xeon processor E5-2600 v2 product family - RDIMMs
and LRDIMMs)
DIMM
specification
RDIMM LRDIMM
Rank Single rank Dual rank Quad rank
Part numbers 00D5024 (4 GB)
00D5036 (8 GB)
00D5020 (4 GB)
00D5032 (8 GB)
00D5040 (8 GB)
00D5048 (16 GB)
46W0761 (32 GB)**
Rated speed 1600 MHz 1866 MHz 1866 MHz 1866 MHz
Rated voltage 1.35 V 1.5 V 1.5 V 1.5 V
Operating voltage 1.35 V 1.5 V 1.5 V 1.5 V 1.5 V
Max qty supported** 24 24 24 24 24
Max DIMM capacity 8 GB 8 GB 8 GB 16 GB 32 GB
Max memory capacity 192 GB 192 GB 192 GB 384 GB 768 GB
Max. memory at rated speed None 128 GB 64 GB 128 GB 256 GB
Maximum operating speed
1 DIMM per channel 1333 MHz 1600 MHz 1866 MHz 1866 MHz 1866 MHz
2 DIMMs per channel 1333 MHz 1600 MHz 1600 MHz 1600 MHz 1600 MHz
3 DIMMs per channel 800 MHz 1066 MHz 1066 MHz 1066 MHz 1066 MHz
* Support is planned for later in 2013.
** The maximum quantity that is supported is shown for two processors installed.