Technical data

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Chapter 2: Chassis Tour
Star Router Board
The Star Router board is used in deskside systems that have three or four Node boards.
The Star Router is always paired with a Rack Router board for proper operation. This
cost-effective router board provides connections with all the Node boards in a module
but cannot be used for CrayLink Interconnect linking. The Star Router has one external
connector which connects to a port on the companion CrayLink Interconnect router
board through a jumper.
Rack Router
The Rack Router boards provide CrayLink Interconnection in a rack system. This router
board can support configurations with up to 64 processors (see Chapter 4, “System
Configurations”). The Rack Router has six ports that route data at up to 1600 MB/sec
(per port). Three of the ports connect internally. The fourth, fifth, and sixth ports can
connect external routers ports on different modules.
Cray Router
The Cray Router chassis (not shown) is used for CrayLink connectivity for configurations
with up to 128 processors. The Cray Router comes in two modules that house additional
router boards to provide interconnection fabric support for systems with more than
64 processors.
Power Distribution Unit (PDU)
The PDU supplies 220 volts for the rack and provides a common AC connection source
for all the modules and other peripheral devices.
Note: The power supply in the system module is auto-ranging from 110 to 220 volts.
CrayLink Interconnect
The CrayLink Interconnect and the Xpress link s are the cabled interface that runs
between Rack Router boards (see Figure 2-10). These cables provide a high speed
(1600 MB/sec), scalable interconnection between different modules. These cables also
supply physical link redundancy so that if a link fails, another link can take its place.