IBM System x3650 M4 Product Manual page 10

Maximum number of ranks 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 the server depends on the number of CPUs,

DIMM type, rank, and operating voltage, as shown in the "Max. qty supported" row in Table 4.
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 "Max. operating
speed" section in Table 4.
Table 4. Maximum memory speeds
DIMM type UDIMM
DIMM
specification
Rank Dual rank
Rated speed 1333 MHz
Rated voltage 1.35 V
Operating voltage 1.35 V 1.5 V 1.35 V 1.5 V 1.5 V
Max. qty 16 16
supported*
Max. DIMM 4 GB 4 GB
capacity
Max. memory 64 GB 64 GB 64 GB 96 GB 96 GB
capacity
Max. memory 32 GB 64 GB 64 GB 64 GB 64 GB
at max. speed
Max. operating _____ _____
speed _ _
1 DIMM per 1333 1333
channel MHz MHz
2 DIMMs per 1066 1333
channel MHz MHz
3 DIMMs per NS** NS**
channel
* Maximum quantity supported is shown for two processors installed. When one processor is installed, the maximum
quantity supported is a half of the quantity that is shown. Shaded cells indicate when all DIMM sockets can be
occupied.
** NS = Not Supported
IBM System x3650 M4
RDIMM
Single rank Dual rank
1333 MHz 1600 1333 MHz
MHz
1.35 V 1.5 V 1.35 V
1.35 V 1.5 V
16 24 24 16
4 GB 4 GB 4 GB 16 GB 16 GB 8 GB
256 GB 384 GB 192 GB
256 GB 256 GB 128 GB
_____ _____ ______ ______
_ _ _
1333 1333 1600 1333
MHz MHz MHz MHz
1333 1333 1600 1333
MHz MHz MHz MHz
NS** 1066 1066 NS**
MHz MHz
Quad rank
1600 1066 MHz
MHz
1.5 V 1.35 V
1.5 V 1.35 V 1.5 V
24 24 16 16
8 GB 8 GB
128 GB 128 GB 384 GB
128 GB 64 GB 384 GB
______ _______ ______ ______
_ _ _
1333 1600 800 1066
MHz MHz MHz MHz
1333 1600 800 800
MHz MHz MHz MHz
1066 1066 NS** NS**
MHz MHz
HCDIMM LRDIMM
Dual rank Quad rank
1333 MHz 1333 MHz
1.5 V 1.35 V
1.5 V 1.35 V 1.5 V
24 24 24
16 GB 32 GB 32 GB
768 GB 768 GB
256 GB 512 GB
_______ ______ ______
_ _
1333 1333 1333
MHz MHz MHz
1333 1066 1333
MHz MHz MHz
1333 1066 1066
MHz MHz MHz
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