About System Memory
The system’s main logic board provides eight slots for high-capacity dual in-line memory modules (DIMMs), divided into two groups of four DIMMs each that may be subdivided again into four logical banks. For the DIMM bank organization and numbering scheme, see the table on next page, or see “DIMM Failure” on page 196.
The system supports Sun standard 200-pin, 3.3-volt, 60-nanosecond memory modules. Modules of 128-, 256-, 512-, or 1024-Mbyte capacity can be installed in the system. Total main memory capacity is expandable up to 8 Gbytes.
Memory modules are delicate. Ensure that you take appropriate precautions to avoid damaging them through electrostatic discharge. The memory modules must be replaced or installed by a qualified service provider. For information about removing and installing DIMMs, see the Sun Fire 280R Server Service Manual.
Configuration Rules
The following memory configuration rules apply to your system:
■At least one memory group consisting of 4 slots (slots J0101, J0203, J0305, and J0407; or slots J0100, J0202, J0304, and J0406) must be filled for the system to boot.
■All DIMMs in a group must be of the same type.
Note –DIMM capacities can differ from one group to the next—for example, four 128-Mbyte DIMMs installed in group 0 and four 256-Mbyte DIMMs installed
in group 1 is permissible, but performance may be impacted.
Caution –DIMMs are made of electronic components that are extremely sensitive to static electricity. Static from your clothes or work environment can destroy the modules. Do not remove any DIMM from its antistatic packaging until you are ready to install it on the system board. Handle the modules only by their edges. Do not touch the components or any metal parts. Always wear a grounding strap when you handle the modules.
