Technical data

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Chapter 2: Chassis Tour
Table 2-2 lists a description of the connectors on the BaseIO.
CPU Node Board
Figure 2-7 shows the location of the CPU Node board in the chassis. The Node board is
the main processing board in the SGI 2400 and 2800 systems. An individual system
module may have up to four Node boards. Figure 2-7 also shows the required Node
board slot positions in a module. The first Node board must be installed in the rightmost
slot (as you face the rear of the chassis). Additional Node boards are added sequentially
to the left.
The Node board consists of these major components:
• 64-bit CPU microprocessors
• sixteen slots of main memory
• eight slots of optional directory memory
• one Hub ASIC
64-bit Processors
The superscalar 64-bit CPU is the main processor for the SGI 2400 and 2800 servers. There
can be one or two 64-bit CPUs on each Node board. You may hear a module or rack
referred to as an 8“P” or 16“P” system. The P stands for processor. An 8P system has
eight processors.
Main Memory
The SGI 2400 and 2800 use SDRAMs mounted on dual inline memory modules (DIMMs)
for main memory. A CPU Node board can have from 64 MB to 4 GB of main memory.
Memory upgrades are available in 64, 128, and 512 MB increments.
Table 2-2 BaseIO Connectors
Connector Type Connector Description Connector Function
100-Base T 8-pin Jack 100-Mb per second Ethernet
Serial 9-pin DIN RS-232 and 422 Serial
SCSI 68-pin (FAST-20) Ultra SCSI (Single-ended)