NEC Express5800 Series User Manual page 66

Chapter 2 Preparations
Memory Lock Step feature can be used under the following conditions:
•
Install DIMMs in DIMM socket to configure a Lock Step set.
• All the installed DIMMs should have the same capacity.
• See Chapter 2 (1. System BIOS) in "Maintenance Guide" to change parameters as shown below.
Advanced → Memory Configuration → Memory RAS Mode → Change to LockStep.
•
After restart, run SETUP again, and check if "Lock Step" is displayed for the following parameter.
Advanced → Memory Configuration → Memory Information → CPUx_DIMMx Status
•
Installation order depends on CPU configuration. See the figure below.
1CPU 2CPU
configuration configuration
2 3
4 7
2 3
4
7
3 5
1
1
3 5
1 1
4
8
4
8
6
2
6
2
Memory Lock Step cannot be configured in the following cases:
•
Memory Lock Step between memory channels of different memory controllers (CPU)
•
Memory Lock Step within the same memory channel
Notes on Configuring Lock Step
In Memory Lock Step configuration, Memory RAS Mode menu is changed from "Lock Step" to "Independent"
in the following cases:
•
When you additionally install DIMMs that unable to configure Memory Lock Step
•
When you remove DIMMs that takes down Memory Lock Step
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CPU1_DIMM 3
CPU1_DIMM 7
CPU1_DIMM 4
CPU1_DIMM 8
CPU1_DIMM 6
CPU1_DIMM 2
CPU1_DIMM 5
CPU1_DIMM 1
CPU2_DIMM 3
CPU2_DIMM 7
CPU2_DIMM 4
CPU2_DIMM 8
CPU2_DIMM 6
CPU2_DIMM 2
CPU2_DIMM 5
CPU2_DIMM 1
Express5800/R120g-1E User's Guide
1. Installing Internal Options