IBM RS/6000 Enterprise Server M80, Service Manual

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System Memory
Two slots are available for system memory riser cards. The system memory riser cards are located for
easy access in the CEC drawer. (These slots are shown in “System Board Locations” on page 18.) Each
memory riser card has 32 DIMM slots.
Four sizes of DIMMs are available: 128 MB, 256 MB, 512 MB and 1 GB. In addition, certain 32 MB
DIMMS from earlier RS/6000 systems can also be used.
Riser Card Memory Placement Rules
The rules for one-way processor memory are as follows:
v Memory octals must contain DIMM modules of equal memory size.
v
You must have at least one memory riser card populated with 8 DIMMs totaling 1 GB.
v Populate the memory card starting from the bottommost available slot of each eight-slot group. (see
“Memory Riser Card and Memory DIMM Locations” on page 19.)
v
If you have two memory riser cards installed, distribute the memory evenly (maintaining octals) between
the two risers.
Chapter 1. Reference Information
23