Pcie Switch; Pcie X1 Expansion; Figure 2-11: Pcie Switch - Global American 3307800 User Manual

2.6.3 PCIe Switch

The AMD RS-690 supports four PCIe x1 lanes. One of the AMD 690G PCIe x1 lanes is
interfaced to an 8-lane 5-port IDT 89HPES8T5 PCIe switch that performs PCIe packet
switching. The PCIe has four PCIe x1 output ports. Two of these ports are interfaced to two
Broadcom PCIe GbE controllers and two are interfaced to a golden finger on the bottom of
the backplane to provide additional PCIe x1 expandability.

Figure 2-11: PCIe Switch

The specifications for the IDT 89HPES8T5 PCIe switch are listed below:
2.5Gbps PCIe lanes
Low-latency cut-through switch architecture
Support for Max Payload Size up to 256 bytes
PCI Express Base Specification Revision 1.1 compliant

2.6.4 PCIe x1 Expansion

The 3307800 has four PCIe x1 expansion channels interfaced to four PCIe x1 connectors
on a backplane through a golden finger on the bottom of the CPU card. Two of the
expansion PCIe x1 lanes come from the AMD 690G Northbridge chipset and two PCIe x1
lanes come from the IDT 89HPES8T5 PCIe switch.
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