Lenovo TD100X manual Branch 0 and branch 1 operate independently

changes. For more information on the Configuration/Setup Utility program, see the User Guide. When you use online-spare memory, you must consider the following information:

-You cannot enable online-spare memory while the server is operating in mirroring mode.

-The minimum memory configuration is two single-rank DIMMs installed in branch 0, DIMM connector 1 (in channel 0) and connector 4 (in channel 1); however, online-sparing is not supported with this configuration.

-To support online-sparing in branch 0, you must add a second pair of DIMMs. The spare pair of DIMMs can be single-rank or double-rank and must be the same speed, type, size (or larger), and technology as the failed pair of DIMMs. The spare pair must be installed in branch 0, DIMM connector 2 (in channel 0) and connector 5 (in channel 1). However, if the DIMMs are double-rank and you install the spare pair of DIMMs in branch 1, DIMM connector 7 (channel 2) and connector 10 (channel 3) rather than branch 0, then branch 1 will support online-sparing and branch 0 will not.

-Branch 0 and branch 1 operate independently.

v The following notes apply when the server operates in non-mirroring mode (normal mode):

–DIMMs must be installed in matched pairs. If you install a second pair of DIMMs in DIMM connector 7 and DIMM connector 10, they do not have to be the same size, speed, type, and technology as the DIMMs in DIMM connector 1 and DIMM connector 4. However, the size, speed, type, and technology of the DIMMs that you install in DIMM connector 7 and DIMM connector 10 must match each other.

–The following table shows the DIMM upgrade configuration sequence for operating in non-mirroring mode (normal mode).

Table 16. DIMM upgrade configuration sequence in non-mirroring mode (normal)

Number of DIMMs	DIMM connectors
2	1, 4
4	1, 4, 7, 10
6	1, 4, 7, 10, 2, 5
8	1, 4, 7, 10, 2, 5, 8, 11
10 (ThinkServer TD100x Machine Types	1, 4, 7, 10, 2, 5, 8, 11, 3, 6
4203, 4204, 4205, and 4206)
12 (ThinkServer TD100x Machine Types	1, 4, 7, 10, 2, 5, 8, 11, 3, 6, 9, 12
4203, 4204, 4205, and 4206)

Note: For ThinkServer TD100 models (Machine Types 6398, 6399, 6419, 6429, 4203, and 4206), DIMM connectors 3, 6, 9, and 12 are not functional. Do not install DIMMs in these connectors.

vThe amount of usable memory will be reduced depending on the system configuration. A certain amount of memory must be reserved for system resources. To view the total amount of installed memory and the amount of configured memory, run the Configuration/Setup Utility program and select System Summary from the menu. For additional information, see the User Guide.

vWhen you restart the server after adding or removing a DIMM, the server displays a message that the memory configuration has changed.

100ThinkServer TD100 and TD100x: Hardware Maintenance Manual