Power Supply Considerations - IBM System x3850 X5 Implementation Manual

installed in the server. To control the boot sequence, from within F1-Setup, select System
Settings  Device and I/O Protest Option ROM Execution Order. Figure 6-25 shows what
the panel looks like after pressing Enter on the list of possible choices. Use the up and down
arrow keys to select a specific entry to move and use the plus or minus keys to move the item
up or down the list.
Figure 6-25 Set Option ROM Execution Order maintenance panel

6.7 Power supply considerations

Most models of the System x3850 X5 ship with two power supplies that will support the entire
server with redundant power regardless of the configuration.
When the server loses one of the two power supplies, the server will report the following
warning in the system event log:
"Non-redundant: Sufficient Resources for Redundancy Degraded"
The MAX5 also comes with two power supplies. If power fails in the MAX5, the server will
power off. Powering the server back on will not be possible unless the MAX5 has power or
until both QPI cables have been disconnected from the server, after removing ac power from
the server. Be careful to ensure that both the MAX5 and the server to which it is attached are
plugged into the same common power sources.
When two x3850 X5 servers are connected as a single complex, the loss of total ac power on
either node will power both nodes down. The primary node will not power on unless ac power
is supplied to the secondary node or the QPI cables are completely disconnected from the
primary node.
You want to ensure that half of the power supplies of both units are plugged into one utility
power source and that the remaining half are plugged into a separate utility power source.
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Chapter 6. IBM System x3850 X5 and x3950 X5