Dell PowerEdge C8000 Hardware Owner's Manual page 83

Boundaries of PSU Configuration
PSU Number
4
3
2
The number of power supplies required for PSU configuration is determined by the following formula:
X + N, where X is the required PSU and N is the redundant PSU.
Required PSU (X)
4
3
2
2
2
1
Using the System Setup Program
Redundant PSU (N)
0
1
2
1
0
1
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