IBM X3950 X5 Problem Determination And Service Manual page 146

v The server supports an additional 512 GB of memory when the 32-DIMM
v The server supports memory sparing. Memory sparing reserves memory
v At least one memory card with one pair of DIMMs must be installed for the
v When you install additional DIMMs on a memory card, be sure to install them
v You do not have to save new configuration information to the IMM when you
v When you restart the server after you add or remove a DIMM, the server
v Memory cards in connectors 1 and 2 support microprocessor 1, memory cards in
v There are four memory power buses, which are split among the eight memory
v Populate the memory-card connectors to match the microprocessor installation,
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IBM System x3850 X5 and x3950 X5 Types 7145, 7146, 7143, and 7191: Problem Determination and Service Guide
that your server supports the memory card that you are installing, look at the
label on the top of the memory card. If the label does not state that the memory
card can be used only in machine types 7143 and 7191, the memory card can be
used only in machine types 7145 and 7146.
optional IBM MAX5 for System x memory expansion module is attached to the
server.
capacity for failover in the event of a DIMM failure, and the reserved capacity is
subtracted from the total available memory. Memory sparing provides less
redundancy than memory mirroring does. If a predetermined threshold of
correctable errors is reached the contents of the failing DIMM are copied to the
spare memory, and the failing DIMM or rank is disabled. To enable memory
sparing through the Setup utility, select System Settings > Memory. (You cannot
use memory mirroring and memory sparing at the same time.)
server to operate.
in pairs. The DIMMs in each pair must match each other.
install or remove DIMMs. The only exception is if you replace a DIMM that was
designated as disabled in the Setup utility Memory Settings menu. In this case,
you must re-enable the row in the Setup utility or reload the default memory
settings.
displays a message that the memory configuration has changed.
connectors 3 and 4 support microprocessor 2, memory cards in connectors 5 and
6 support microprocessor 3, and memory cards in connectors 7 and 8 support
microprocessor 4.
cards.
in the following order: 1, 7, 3, 5, 2, 8, 4, 6. (Microprocessors must be installed in
the following order: 1, 4, 2, and 3.) The following illustration shows the locations
of the memory-card and microprocessor connectors.