Lenovo ThinkServer RD450 User Manual And Hardware Maintenance Manual page 85

• All memory modules to be installed must be the same type. Your server supports the following types
of memory modules:
– DDR4 RDIMM with ECC technology
– DDR4 LRDIMM with ECC technology
• When you install memory modules with different ranks in one channel, start from the farthest memory slot
in the channel. Install the memory module that has the most ranks first.
• When you install memory modules with different frequencies into the memory slots for the same
microprocessor, all the memory modules run at the lowest frequency.
• It is recommended that you install the high-frequency memory modules into the memory slots for the
same microprocessor to ensure high performance.
The following illustration helps you to locate the memory slots on the system board. The following illustration
shows the system board with two installed microprocessors (also known as CPU).
Figure 39. Memory slots on the system board
The following table provides information about the memory module installation rules for servers that have
only one microprocessor (CPU1) installed. The "X" mark indicates the memory slots into which the memory
modules should be installed in different situations.
Table 1. Memory module installation rules for servers with one microprocessor
CPU1 DIMM A1
1 DIMM
2 DIMMs
4 DIMMs
8 DIMMs
CPU1 DIMMC1
CPU1 DIMMC2
CPU1 DIMMD1
CPU1 DIMMD2
CPU1 DIMMB2
CPU1 DIMMB1
CPU1 DIMMA2
CPU1 DIMMA1
A2 B1
X
X X
X X
X X X
CPU2 DIMMC1
CPU2 DIMMC2
CPU2 DIMMD1
CPU2 DIMMD2
CPU2 DIMMB2
CPU2 DIMMB1
CPU2 DIMMA2
CPU2 DIMMA1
B2 C1 C2
X
X X X
Chapter 6
D1 D2
X
X X
71
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Replacing hardware