Compaq AlphaServer ES45 1B Owner's Manual page 126

System Models 1B, 2B, and 3B have a minimum configuration of one power
supply and the Model 2 has a minimum configuration of two power supplies.
Minimum Power Supply Configurations
The following is the maximum system configuration for Models 1B, 2B, and 3B
with one power supply:
•
Two CPUs
•
One storage cage (six hard drives)
•
Four to sixteen DIMMs
Two Power Supply Configuration. Two power supplies are required if the sys-
tem has more than two CPUs, a second storage cage, or more than 16 DIMMs.
Redundant Power Supply. If a power supply fails, the redundant supply
provides power and the system continues to operate normally. A third power
supply adds redundancy for an entry-level system.
Recommended Installation Order. Generally, power supply 0 is installed
first, power supply 1 second, and power supply 2 third, but the supplies can be
installed in any order. See Figure 4–5. The power supply numbering corre-
sponds to the numbering displayed by the SRM show power command.
4-16 ES45 Owner's Guide