IBM System x3650 M4 Product Manual page 20

Mixing 1.5 V and 1.35 V DIMMs is supported; in such a case, all DIMMs operate at 1.5 V.

Maximum number of ranks per one channel is eight (with the exception of Load Reduced DIMMs and

HyperCloud DIMMs where more than eight ranks are supported, because one quad-rank LRDIMM or
HCDIMM provides the reduced electrical load on a memory bus).
The maximum quantity of DIMMs that can be installed in the server depends on the number of CPUs,

DIMM type, rank, and operating voltage, as shown in the "Max. qty supported" row in Table 5.
All DIMMs in the server operate at the same speed, which is determined as the lowest value of:

Memory speed that is supported by the specific CPU.

Lowest of maximum operating speeds for 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 table.
The following table (Parts 1, 2, 3, and 4) 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)
DIMM
specification
Rank
Part numbers
Rated speed
Rated voltage
Operating voltage
Max qty supported*
Max DIMM capacity
Max memory capacity
Max. memory at rated speed
Maximum operating speed
1 DIMM per channel
2 DIMMs per channel
3 DIMMs per channel
* The maximum quantity that is supported is shown for two processors installed.
IBM System x3650 M4
Single rank
00D5024 (4 GB) 00D5020 (4 GB)
00D5036 (8 GB) 00D5032 (8 GB)
1600 MHz
1.35 V
1.35 V 1.5 V
24 24
8 GB 8 GB
192 GB 192 GB
None 128 GB
1333 MHz 1600 MHz
1333 MHz 1600 MHz
800 MHz 1066 MHz
RDIMM
00D5044 (8 GB)
46W0672 (16 GB)
1866 MHz 1600 MHz
1.5 V 1.35 V
1.5 V 1.35 V
24 24
8 GB 16 GB
192 GB 384 GB
64 GB None
1866 MHz 1333 MHz
1600 MHz 1333 MHz
1066 MHz 800 MHz
Dual rank
00D5048 (16 GB)
1866 MHz
1.5 V
1.5 V 1.5 V
24 24
16 GB 16 GB
384 GB 384 GB
256 GB 256 GB
1600 MHz 1866 MHz
1600 MHz 1866 MHz
1066 MHz 1066 MHz
20