Service manual

1-80 AlphaServer GS80/160/320 Service Manual
1.21 PCI Subsystem
The I/O subsystem consists of the local and remote I/O risers and the
PCI box to which they are attached. There are two types of PCI boxes:
a master PCI box and an expansion PCI box. The master PCI box has
the devices necessary to test and boot the system; the expansion PCI
box does not.
1.21.1 PCI I/O Subsystem Interconnect
The PCI I/O subsystem is connected to QBBs through local and remote
I/O riser modules and their cables.
Figure 1– 36 I/O Subsystem Module and Cable Interconnect
PCI
Backplane
Standard
I/O Module
CSB Node
ID Module
Standard I/O
Cable Interconnect
Module
Remote I/O
Riser Module
Local I/O
Riser Module
QBB
Backplane
Remote I/O
Riser Module
PK1267