Table of Contents
Advertisement
Table 24. Independent mode with two processors and different capacity memory modules (processor 2)
Total
DIMMs
17
18
19
19
4
19
8
17
19
1,2
16
17
19
1,2
24
17
18
19
1,2
32
Notes:
1. DIMM configurations that support Sub NUMA Clustering (SNC), which can be enabled via UEFI.
2. DIMM configurations that support Software Guard Extensions (SGX), see "Enable Software Guard
Extensions (SGX)" on page 157 to enable this feature.
Memory mirroring mode
Memory-mirroring mode provides full memory redundancy while reducing the total system memory capacity
in half. Memory channels are grouped in pairs with each channel receiving the same data. If a failure occurs,
the memory controller switches from the DIMMs on the primary channel to the DIMMs on the backup
channel. The DIMM installation order for memory mirroring varies based on the number of processors and
DIMMs installed in the server.
Attention: Memory mirroring guidelines:
• Mirroring can be configured across two channels.
• Both channels must be populated in each iMC.
• The total memory size of the primary and secondary channels must be the same.
• Memory mirroring is supported when PMEMs are installed and set to 100% App Direct Mode.
• Memory mirroring mode is limited to DDR4 memory modules only, PMEM memory mirroring is not
supported in App Direct Mode.
Channels
Slots
Identical DIMM installation required
Identical DIMM installation required for
full channel mirroring
Note: When adding one or more DIMMs during a memory upgrade, you might need to remove some DIMMs
that are already installed to new locations.
Mirror memory mode with one processor
Table 25. Mirror mode with one processor
Total
DIMMs
1
2
1
8*
1
2
16*
ThinkSystem ST650 V2 Setup Guide
66
20
21
22
23
21
21
21
23
20
21
23
20
21
22
23
3
4
5
6
7
3
5
7
3
4
5
6
7
Processor 2
25
26
27
28
24
28
26
28
24
25
26
28
24
25
26
27
28
Channel 0
Slot 1
Slot 0
Y
Y
Y
Processor 1
8
9
10
11
12
10
12
8
9
10
11
12
Total
DIMMs
29
30
31
32
30
30
32
29
30
32
29
30
31
32
Channel 1
Slot 1
Slot 0
Y
Y
Y
Total
DIMMs
13
14
15
16
14
16
13
14
15
16
4
8
1,2
16
1,2
24
1,2
32
8*
16*
Advertisement
Table of Contents
