Silicon Graphics Origin 3900, User Manual, Page: 68 / 292

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2: System Overview
Standard System Components
The SGI Origin 3900 server features the following standard components (see Figure 2-4):
• Cx-brick - This compute brick contains 4, 8, 12, or 16 MIPS processors, 1 GB to 32 GB
of memory, and a router board. The Cx-brick is equivalent to four C-bricks and one
R-brick in one enclosure. For more information about the Cx-brick, see Chapter 3,
“Cx-brick”.
• IX-brick - This I/O brick is a Crosstalk-to-PCI-X based I/O expansion subsystem
that provides the base I/O functionality for the system. For more information about
the IX-brick, see Chapter 4, “IX-brick”.
• R-brick - This router brick transfers messages between the Cx-bricks via the
NUMAlink interconnect. The R-brick is required for systems that contain more than
four Cx-bricks. For more information about the R-brick, see Chapter 7, “R-brick”.
• L2 controller - This rack-level controller manages the bricks within a rack (not
shown in Figure 2-4). For more information about the L2 controller, see Chapter 8,
“System Control”.
• Power components - The power components of the Origin 3900 server consist of
power distribution units (PDUs) and power bays. The PDUs filter input power,
protect against over-current conditions, and remove power from the racks (not
shown in Figure 2-4). The power bay inputs AC voltage and outputs 48 VDC and 12
VDC standby voltage to the bricks within a rack. For more information about these
power components, see Chapter 9, “Power Components”.
• Rack - This industry-standard 19-inch rack contains 39 units (Us) of vertical space
that can seat bricks and power bays. (Each U is equivalent to 1.75 inches.) This rack
uses two parallel L-shaped mounting rails to support each brick within the rack.
Figure 2-3 L-shaped Mounting Rails
19 in.
L-shaped horizontal
mounting rails