Installing a DIMM

Use this information to install a DIMM.

About this task

This component can be installed as an optional device or as a CRU. The installation procedure is the same for the optional device and the CRU.

After you install or remove a DIMM, you must change and save the new configuration information by using the Setup utility. When you turn on the compute node, a message indicates that the memory configuration has changed. Start the Setup utility and select Save Settings (see Using the Setup utility for more information) to save changes.

If you are installing a DIMM as a result of a DIMM failure, you might have to reenable the DIMM. To re-enable the DIMM, complete the following steps:

1. Verify that the amount of installed memory is the expected amount of memory through the operating system, by watching the monitor as the compute node starts, by using the CMM sol command, or through IBM® Flex System Manager management software.
   • For more information about the CMM sol command, see the IBM Flex System Chassis Management Module: Command-Line Interface Reference Guide.
   • For more information about IBM Flex System Manager management software, see the the IBM Flex System Manager Software Installation and Service Guide.
2. Run the Setup utility to reenable the DIMMs (see Using the Setup utility for more information).

The compute node has a total of 48 dual inline memory module (DIMM) connectors. The compute node supports low-profile (LP) DDR3 DIMMs with error-correcting code (ECC) in 4 GB, 8 GB, 16 GB and 32 GB capacities.

The following illustration shows the system-board components, including the DIMM connectors.

The memory is accessed internally through 16 channels (four channels for each microprocessor). Each channel contains three DIMM connectors. Each channel can have a maximum of eight ranks. The following table lists each channel and shows which DIMM connectors are in the channel.

Table 1. Memory-channel configuration

Microprocessor	Memory channel	DIMM connectors
Microprocessor 1	Channel 1	1, 2, and 3
	Channel 0	4, 5, and 6
	Channel 2	7, 8, and 9
	Channel 3	10, 11, and 12
Microprocessor 2	Channel 1	13, 14, and 15
	Channel 0	16, 17, and 18
	Channel 2	19, 20, and 21
	Channel 3	22, 23, and 14
Microprocessor 3	Channel 2	25, 26, and 27
	Channel 3	28, 29, and 30
	Channel 1	31, 32, and 33
	Channel 0	34, 35, and 36
Microprocessor 4	Channel 2	37, 38, and 39
	Channel 3	40, 41, and 42
	Channel 1	43, 44, and 45
	Channel 0	46, 47, and 48

The following notes describe information that you must consider when you install memory:

• You cannot mix RDIMMs, LRDIMMs and UDIMMs in the same compute node.
• UDIMMs are not supported at three DIMMs per channel.
• A total of eight ranks on each channel is supported.
• If a quad-rank DIMM is installed, install it in the connector at the end of the memory channel.
• If a channel has one or more quad-rank RDIMMs, only two DIMMs per channel is supported. The quad-rank, eight rank per channel limitation only applies to RDIMMs. Quad-rank LRDIMMs can be installed at three DIMMs per channel since the processor recognizes LRDIMMs as dual-rank DIMMs.

There are three memory modes:

• Independent-channel mode: Independent-channel mode provides a maximum of 384 GB of usable memory per processor and 1536 GB of usable memory with all four processors installed using 32 GB DIMMs. DIMMs must be first installed in the last physical DIMM connector of each channel. DIMMs should also be installed one DIMM per channel first. The best performance is seen with an even memory distribution among all four channels on the microprocessor. DIMMs can be installed without matching sizes. Individual channels may run at different DIMM timings, but all channels must run at the same interface frequency. DIMMs with different timing parameters can be installed in different connectors of the same channel, but only timings that support the slowest DIMM are applied to all the DIMMs. Faster DIMMs operate at timings that are supported by the slowest installed DIMM.
• Mirrored-channel mode: In mirrored-channel mode, memory is installed in pairs. Both DIMMs in a pair must be identical in capacity, type, and rank count. The channels are grouped in pairs with each channel receiving the same data. One channel is used as a backup of the other, which provides redundancy. In mirrored-channel mode, memory must be installed in pairs. The memory content is mirrored between channel 0 and channel 1 and between channel 2 and channel 3. Mirrored-channel mode requires that channel 0 and channel 1, and channel 2 and channel 3 are be populated identically in regard to size and organization. DIMM connector populations within a channel do not have to be identical, but the same DIMM connector location across channel 0 and channel 1 and across channel 2 and channel 3 must be populated in the same way. The effective memory that is available to the system is only half of what is installed.
• Rank-sparing mode: In rank-sparing mode, one memory DIMM rank serves as a spare of the other ranks on the same channel. The spare rank is held in reserve and is not used as active memory. The spare rank must have identical or larger memory capacity than all the other active DIMM ranks on the same channel. After an error threshold is surpassed, the contents of that rank are copied to the spare rank. The failed rank of DIMMs is taken offline, and the spare rank is put online and used as active memory in place of the failed rank.
  The following notes describe additional information that you must consider when you select rank-sparing memory mode:

  • Memory sparing on one channel is independent of the sparing on all other channels.
  • You can use the Setup utility to determine the status of the DIMM ranks.
  • If only one DIMM is present in a channel and the DIMM is dual or single rank, then sparing mode should not be enabled.

  Rank-sparing on one channel is independent of the sparing on all other channels. You can use the Setup utility to determine the status of the DIMM ranks.

Install DIMMs in the order that is indicated in the following table for independent-channel mode.

Table 2. DIMM population sequence for independent-channel mode

Number of DIMMs installed	1 microprocessor installed	2 microprocessors installed	4 microprocessors installed
1	DIMM 4	DIMM 4	DIMM 4
2	DIMMs 1 and 4	DIMMs 4 and 16	DIMMs 4 and 16
3	DIMMs 1, 4, and 9	DIMMs 1, 4, and 16	DIMMs 4, 16, and 33
4	DIMMs 1, 4, 9, and 12	DIMMs 1, 4, 13, and 16	DIMMs 4, 16, 33, and 45
5	DIMMs 1, 4, 9, 5, and 12	DIMMs 1, 4, 9, 13, and 16	DIMMs 1, 4, 16, 33, and 45
6	DIMMs 1, 2, 4, 9, 5, and 12	DIMMs 1, 4, 9, 13, 16, and 21	DIMMs 1, 4, 13, 16, 33, and 45
7	DIMMs 1, 2, 4, 8, 9, 5, and 12	DIMMs 1, 4, 9, 12, 13, 16, and 21	DIMMs 1, 4, 13, 16, 33, 36, and 45
8	DIMMs 1, 2, 4, 8, 9, 5, 11, and 12	DIMMs 1, 4, 9, 12, 13, 16, 21, and 24	DIMMs 1, 4, 13, 16, 33, 36, 45, and 48
9	DIMMs 1, 2, 4, 6, 8, 9, 5, 11, and 12	DIMMs 1, 4, 5, 9, 12, 13, 16, 21, and 24	DIMMs 1, 4, 9, 13, 16, 33, 36, 45, and 48
10	DIMMs 1, 2, 3, 4, 6, 8, 9, 5, 11, and 12	DIMMs 1, 4, 5, 9, 12, 13, 16, 17, 21, and 24	DIMMs 1, 4, 9, 13, 16, 21, 33, 36, 45, and 48
11	DIMMs 1, 2, 3, 4, 6, 7, 8, 9, 5, 11, and 12	DIMMs 1, 2, 4, 5, 9, 12, 13, 16, 17, 21, and 24	DIMMs 1, 4, 9, 13, 16, 21, 28, 33, 36, 45, and 48
12	DIMMs 1, 2, 3, 4, 6, 7, 8, 9, 10, 5, 11, and 12	DIMMs 1, 2, 4, 5, 9, 12, 13, 14, 16, 17, 21, and 24	DIMMs 1, 4, 9, 13, 16, 21, 28, 33, 36, 40, 45, and 48
13		DIMMs 1, 2, 4, 5, 8, 9, 12, 13, 14, 16, 17, 21, and 24	DIMMs 1, 4, 9, 12, 13, 16, 21, 28, 33, 36, 40, 45, and 48
14		DIMMs 1, 2, 4, 5, 8, 9, 12, 13, 14, 16, 17, 20, 21, and 24	DIMMs 1, 4, 9, 12, 13, 16, 21, 24, 28, 33, 36, 40, 45, and 48
15		DIMMs 1, 2, 4, 5, 8, 9, 11, 12, 13, 14, 16, 17, 20, 21, and 24	DIMMs 1, 4, 9, 12, 13, 16, 21, 24, 25, 28, 33, 36, 40, 45, and 48
16		DIMMs 1, 2, 4, 5, 8, 9, 11, 12, 13, 14, 16, 17, 20, 21, 23, and 24	DIMMs 1, 4, 9, 12, 13, 16, 21, 24, 25, 28, 33, 36, 37, 40, 45, and 48
17		DIMMs 1, 2, 4, 5, 6, 8, 9, 11, 12, 13, 14, 16, 17, 20, 21, 23, and 24	DIMMs 1, 4, 5, 9, 12, 13, 16, 21, 24, 25, 28, 33, 36, 37, 40, 45, and 48
18		DIMMs 1, 2, 4, 5, 6, 8, 9, 11, 12, 13, 14, 16, 17, 18, 20, 21, 23, and 24	DIMMs 1, 4, 5, 9, 12, 13, 16, 17, 21, 24, 25, 28, 33, 36, 37, 40, 45, and 48
19		DIMMs 1, 2, 3, 4, 5, 6, 8, 9, 11, 12, 13, 14, 16, 17, 18, 20, 21, 23, and 24	DIMMs 1, 4, 5, 9, 12, 13, 16, 17, 21, 24, 25, 28, 32, 33, 36, 37, 40, 45, and 48
20		DIMMs 1, 2, 3, 4, 5, 6, 8, 9, 11, 12, 13, 15, 14, 16, 17, 18, 20, 21, 23, and 24	DIMMs 1, 4, 5, 9, 12, 13, 16, 17, 21, 24, 25, 28, 32, 33, 36, 37, 40, 44, 45, and 48
21		DIMMs 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 13, 15, 14, 16, 17, 18, 20, 21, 23, and 24	DIMMs 1, 2, 4, 5, 9, 12, 13, 16, 17, 21, 24, 25, 28, 32, 33, 36, 37, 40, 44, 45, and 48
22		DIMMs 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 13, 15, 14, 16, 17, 18, 19, 20, 21, 23, and 24	DIMMs 1, 2, 4, 5, 9, 12, 13, 14, 16, 17, 21, 24, 25, 28, 32, 33, 36, 37, 40, 44, 45, and 48
23		DIMMs 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 15, 14, 16, 17, 18, 19, 20, 21, 23, and 24	DIMMs 1, 2, 4, 5, 9, 12, 13, 14, 16, 17, 21, 24, 25, 28, 32, 33, 35, 36, 37, 40, 44, 45, and 48
24		DIMMs 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 15, 14, 16, 17, 18, 19, 20, 21, 22, 23, and 24	DIMMs 1, 2, 4, 5, 9, 12, 13, 14, 16, 17, 21, 24, 25, 28, 32, 33, 35, 36, 37, 40, 44, 45, 47, and 48
25			DIMMs 1, 2, 4, 5, 8, 9, 12, 13, 14, 16, 17, 21, 24, 25, 28, 32, 33, 35, 36, 37, 40, 44, 45, 47, and 48
26			DIMMs 1, 2, 4, 5, 8, 9, 12, 13, 14, 16, 17, 20, 21, 24, 25, 28, 32, 33, 35, 36, 37, 40, 44, 45, 47, and 48
27			DIMMs 1, 2, 4, 5, 8, 9, 12, 13, 14, 16, 17, 20, 21, 24, 25, 28, 29, 32, 33, 35, 36, 37, 40, 44, 45, 47, and 48
28			DIMMs 1, 2, 4, 5, 8, 9, 12, 13, 14, 16, 17, 20, 21, 24, 25, 28, 29, 32, 33, 35, 36, 37, 40, 41, 44, 45, 47, and 48
29			DIMMs 1, 2, 4, 5, 8, 9, 11, 12, 13, 14, 16, 17, 20, 21, 24, 25, 28, 29, 32, 33, 35, 36, 37, 40, 41, 44, 45, 47, and 48
30			DIMMs 1, 2, 4, 5, 8, 9, 11, 12, 13, 14, 16, 17, 20, 21, 23, 24, 25, 28, 29, 32, 33, 35, 36, 37, 40, 41, 44, 45, 47, and 48
31			DIMMs 1, 2, 4, 5, 8, 9, 11, 12, 13, 14, 16, 17, 20, 21, 23, 24, 25, 26, 28, 29, 32, 33, 35, 36, 37, 40, 41, 44, 45, 47, and 48
32			DIMMs 1, 2, 4, 5, 8, 9, 11, 12, 13, 14, 16, 17, 20, 21, 23, 24, 25, 26, 28, 29, 32, 33, 35, 36, 37, 38, 40, 41, 44, 45, 47, and 48
33			DIMMs 1, 2, 4, 5, 6, 8, 9, 11, 12, 13, 14, 16, 17, 20, 21, 23, 24, 25, 26, 28, 29, 32, 33, 35, 36, 37, 38, 40, 41, 44, 45, 47, and 48
34			DIMMs 1, 2, 4, 5, 6, 8, 9, 11, 12, 13, 14, 16, 17, 18, 20, 21, 23, 24, 25, 26, 28, 29, 32, 33, 35, 36, 37, 38, 40, 41, 44, 45, 47, and 48
35			DIMMs 1, 2, 4, 5, 6, 8, 9, 11, 12, 13, 14, 16, 17, 18, 20, 21, 23, 24, 25, 26, 28, 29, 31, 32, 33, 35, 36, 37, 38, 40, 41, 44, 45, 47, and 48
36			DIMMs 1, 2, 4, 5, 6, 8, 9, 11, 12, 13, 14, 16, 17, 18, 20, 21, 23, 24, 25, 26, 28, 29, 31, 32, 33, 35, 36, 37, 38, 40, 41, 43, 44, 45, 47, and 48
37			DIMMs 1, 2, 3, 4, 5, 6, 8, 9, 11, 12, 13, 14, 16, 17, 18, 20, 21, 23, 24, 25, 26, 28, 29, 31, 32, 33, 35, 36, 37, 38, 40, 41, 43, 44, 45, 47, and 48
38			DIMMs 1, 2, 3, 4, 5, 6, 8, 9, 11, 12, 13, 14, 15, 16, 17, 18, 20, 21, 23, 24, 25, 26, 28, 29, 31, 32, 33, 35, 36, 37, 38, 40, 41, 43, 44, 45, 47, and 48
39			DIMMs 1, 2, 3, 4, 5, 6, 8, 9, 11, 12, 13, 14, 15, 16, 17, 18, 20, 21, 23, 24, 25, 26, 28, 29, 31, 32, 33, 34, 35, 36, 37, 38, 40, 41, 43, 44, 45, 47, and 48
40			DIMMs 1, 2, 3, 4, 5, 6, 8, 9, 11, 12, 13, 14, 15, 16, 17, 18, 20, 21, 23, 24, 25, 26, 28, 29, 31, 32, 33, 34, 35, 36, 37, 38, 40, 41, 43, 44, 45, 46, 47, and 48
41			DIMMs 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 13, 14, 15, 16, 17, 18, 20, 21, 23, 24, 25, 26, 28, 29, 31, 32, 33, 34, 35, 36, 37, 38, 40, 41, 43, 44, 45, 46, 47, and 48
42			DIMMs 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 23, 24, 25, 26, 28, 29, 31, 32, 33, 34, 35, 36, 37, 38, 40, 41, 43, 44, 45, 46, 47, and 48
43			DIMMs 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 23, 24, 25, 26, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 40, 41, 43, 44, 45, 46, 47, and 48
44			DIMMs 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 23, 24, 25, 26, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 40, 41, 42, 43, 44, 45, 46, 47, and 48
45			DIMMs 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 23, 24, 25, 26, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 40, 41, 42, 43, 44, 45, 46, 47, and 48
46			DIMMs 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 40, 41, 42, 43, 44, 45, 46, 47, and 48
47			DIMMs 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 40, 41, 42, 43, 44, 45, 46, 47, and 48
48			DIMMs 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, and 48

Install DIMMs in the order that is indicated in the following table for mirrored-channel mode.

Table 3. DIMM population sequence for mirrored-channel mode

Number of DIMM pairs installed	1 microprocessor installed	2 microprocessor installed	4 microprocessor installed
1	DIMMs 1 and 41	DIMMs 1 and 41	DIMMs 1 and 41
2	DIMMs 1 and 4, 9 and 121	DIMMs 1 and 4, 13 and 161	DIMMs 1 and 4, 13 and 161
3	DIMMs 1 and 4, 9 and 12, 2 and 51	DIMMs 1 and 4, 13 and 16, 9 and 121	DIMMs 1 and 4, 13 and 16, 33 and 361
4	DIMMs 1 and 4, 9 and 12, 2 and 5, 8 and 111	DIMMs 1 and 4, 13 and 16, 9 and 12, 21 and 241	DIMMs 1 and 4, 13 and 16, 33 and 36, 45 and 481
5	DIMMs 1 and 4, 9 and 12, 2 and 5, 8 and 11, 3 and 61	DIMMs 1 and 4, 13 and 16, 9 and 12, 21 and 24, 2 and 51	DIMMs 1 and 4, 13 and 16, 33 and 36, 45 and 48, 9 and 121
6	DIMMs 1 and 4, 9 and 12, 2 and 5, 8 and 11, 3 and 6, 7 and 101	DIMMs 1 and 4, 13 and 16, 9 and 12, 21 and 24, 2 and 5, and 14 and 171	DIMMs 1 and 4, 13 and 16, 33 and 36, 45 and 48, 9 and 12, 21 and 241
7		DIMMs 1 and 4, 13 and 16, 9 and 12, 21 and 24, 2 and 5, and 14 and 17, 8 and 111	DIMMs 1 and 4, 13 and 16, 33 and 36, 45 and 48, 9 and 12, 21 and 24, 25 and 281
8		DIMMs 1 and 4, 13 and 16, 9 and 12, 21 and 24, 2 and 5, and 14 and 17, 8 and 11, 20 and 231	DIMMs 1 and 4, 13 and 16, 33 and 36, 45 and 48, 9 and 12, 21 and 24, 25 and 28, 37 and 401
9		DIMMs 1 and 4, 13 and 16, 9 and 12, 21 and 24, 2 and 5, and 14 and 17, 8 and 11, 20 and 23, 3 and 61	DIMMs 1 and 4, 13 and 16, 33 and 36, 45 and 48, 9 and 12, 21 and 24, 25 and 28, 37 and 40, 2 and 51
10		DIMMs 1 and 4, 13 and 16, 9 and 12, 21 and 24, 2 and 5, and 14 and 17, 8 and 11, 20 and 23, 3 and 6, 15 and 181	DIMMs 1 and 4, 13 and 16, 33 and 36, 45 and 48, 9 and 12, 21 and 24, 25 and 28, 37 and 40, 2 and 5, 14 and 171
11		DIMMs 1 and 4, 13 and 16, 9 and 12, 21 and 24, 2 and 5, and 14 and 17, 8 and 11, 20 and 23, 3 and 6, 15 and 18, 7 and 101	DIMMs 1 and 4, 13 and 16, 33 and 36, 45 and 48, 9 and 12, 21 and 24, 25 and 28, 37 and 40, 2 and 5, 14 and 17, 32 and 351
12		DIMMs 1 and 4, 13 and 16, 9 and 12, 21 and 24, 2 and 5, and 14 and 17, 8 and 11, 20 and 23, 3 and 6, 15 and 18, 7 and 10, 19 and 221	DIMMs 1 and 4, 13 and 16, 33 and 36, 45 and 48, 9 and 12, 21 and 24, 25 and 28, 37 and 40, 2 and 5, 14 and 17, 32 and 35, 44 and 471
13			DIMMs 1 and 4, 13 and 16, 33 and 36, 45 and 48, 9 and 12, 21 and 24, 25 and 28, 37 and 40, 2 and 5, 14 and 17, 32 and 35, 44 and 47, 8 and 111
14			DIMMs 1 and 4, 13 and 16, 33 and 36, 45 and 48, 9 and 12, 21 and 24, 25 and 28, 37 and 40, 2 and 5, 14 and 17, 32 and 35, 44 and 47, 8 and 11, 20 and 231
15			DIMMs 1 and 4, 13 and 16, 33 and 36, 45 and 48, 9 and 12, 21 and 24, 25 and 28, 37 and 40, 2 and 5, 14 and 17, 32 and 35, 44 and 47, 8 and 11, 20 and 23, 26 and 291
16			DIMMs 1 and 4, 13 and 16, 33 and 36, 45 and 48, 9 and 12, 21 and 24, 25 and 28, 37 and 40, 2 and 5, 14 and 17, 32 and 35, 44 and 47, 8 and 11, 20 and 23, 26 and 29, 38 and 411
17			DIMMs 1 and 4, 13 and 16, 33 and 36, 45 and 48, 9 and 12, 21 and 24, 25 and 28, 37 and 40, 2 and 5, 14 and 17, 32 and 35, 44 and 47, 8 and 11, 20 and 23, 26 and 29, 38 and 41, 3 and 61
18			DIMMs 1 and 4, 13 and 16, 33 and 36, 45 and 48, 9 and 12, 21 and 24, 25 and 28, 37 and 40, 2 and 5, 14 and 17, 32 and 35, 44 and 47, 8 and 11, 20 and 23, 26 and 29, 38 and 41, 3 and 6, 15 and 181
For mirrored-channel mode, the DIMM pair must be identical in size, type, and rank count.

To install a DIMM, complete the following steps:

1. Remove the cover (see Removing the compute node cover).
2. Read the documentation that comes with the DIMM.
3. Remove the air baffle installed over the DIMM connector.
   
4. Locate the DIMM connectors (see System-board connectors). Determine which DIMM connector you want to install the DIMM in.
5. Touch the static-protective package that contains the DIMM to any unpainted metal surface on the Flex System chassis or any unpainted metal surface on any other grounded rack component in the rack in which you are installing the DIMM for at least 2 seconds; then, remove the DIMM from its package.
   
6. Make sure that both retaining clips on the DIMM connector are in the open position.
7. Turn the DIMM so that the DIMM keys align correctly with the DIMM connector on the system board.
   Attention: To avoid breaking the retaining clips or damaging the DIMM connector, handle the clips gently.
8. Press the DIMM into the DIMM connector. The retaining clips lock the DIMM into the connector.
9. Make sure that the small tabs on the retaining clips engage the notches on the DIMM. If there is a gap between the DIMM and the retaining clips, the DIMM has not been correctly installed. Press the DIMM firmly into the connector, and then press the retaining clips toward the DIMM until the tabs are fully seated. When the DIMM is correctly installed, the retaining clips are parallel to the sides of the DIMM.
   
10. Install the air baffle over the DIMM connector.
    Attention:

    • Install the air baffles with the arrow indicating air flow direction pointing to the rear of the compute node.
    • To maintain proper system cooling, do not operate the compute node without air baffles installed over the DIMM connectors.