Intel SGI Altix 450 manual Memory Dimm Group Placement and Guidelines, 121

Replacing IRU Components

Memory DIMM Group Placement and Guidelines

Memory is contained on cards that are referred to as DIMMs (dual inline memory modules). Each individual memory or compute/memory blade can contain four, eight, or twelve DIMMs installed in DIMM slots located on the blade's node board.

These twelve DIMM slots are organized into three groups of four DIMMs each, as shown in

Figure 6-10.

DIMMs are installed one per DIMM slot, and must be installed in groups of four. Figure 6-11 shows an example of the physical DIMM locations within the processor blade assembly.

Follow these guidelines when installing DIMM groups:

•Memory is increased or decreased in four-DIMM group increments only. Each of the four DIMMs that make up a DIMM group must be the same memory size and speed; however, different blades can differ in total memory size.

•The first four DIMMs (group 0) must be in place for the blade’s memory to operate properly.

•Mixing compute/memory blades with different capacity DIMM groups within an IRU is permitted.

•When installing 4 GB DIMMs check with your SGI service representative. Space limitations may require that a maximum of eight 4 GB DIMMs be installed on each blade.

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