IBM System x3400 M3 Types 7378, Installation And User Manual

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DIMM in channel 1, and the spare DIMM in channel 2. The DIMMs must be
identical in size, type, rank, and organization, but not in speed. The channels run
at the speed of the slowest DIMM in any of the channels.
v The maximum available memory is reduced to 2/3 of the installed memory when
memory sparing mode is enabled. For example, if you install 72 GB of memory
using RDIMMs, only 48 GB of addressable memory is available when you use
memory sparing.
The following table shows the installation sequence for installing DIMMs for each
microprocessor and the sparing DIMM in memory online-spare mode:
Table 10. Memory sparing mode DIMM population sequence
DIMMs
Number of installed
microprocessors
DIMM slots
1st set of DIMMs 1 3, 6, 8
2nd set of DIMMs 1 2, 5, 7
3rd set of DIMMs 2 11, 14, 16
4th set of DIMMs 2 10, 13, 15
Notes:
1. The 3rd and 4th sets of DIMMs can be installed right after microprocessor 2 is
installed even 1st and 2nd sets of DIMM slots are not full.
2. DIMM slots 1, 4, 9, and 12 are not used in memory sparing mode.
Installing an optional ServeRAID adapter advanced feature key
To install an optional ServeRAID adapter advanced feature key, complete the
following steps:
1. Read the safety information that begins on page vii and “Installation guidelines”
on page 29.
2. Turn off the server and peripheral devices and disconnect the power cords.
3. Remove the left-side cover (see “Removing the left-side cover” on page 49).
4. Rotate the adapter-retention brackets to the open position.
5. Align the upgrade key with the connector on the ServeRAID adapter and push it
into the connector until it is firmly seated.
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IBM System x3400 M3 Types 7378 and 7379: Installation and User's Guide