Signal Descriptions
146 Intel® Xeon® Processor E5-1600/E5-2600/E5-4600 Product Families
Datasheet Volume One
Note: Refer to the appropriate Platform Design Guide (PDG) for additional implementation details.
6.3 DMI2/PCI Express* Port 0 Signals6.4 Intel QuickPath Interconnect Signals
Note: Refer to the appropriate Platform Design Guide (PDG) for additional implementation details.
PEHPSDA
PCI Express* Hot-Plug SMBus Data: Provides PCI Express* hot-
plug support via a dedicated SMBus interface. Requires an external
general purpose input/output (GPIO) expansion device on the
platform.

Table 6-6. PCI Express* Miscellaneous Signals (Sheet 2 of 2)

Signal Name Description

Table 6-7. DMI2 and PCI Express* Port 0 Signals

Signal Name Description
DMI_RX_DN[3:0]
DMI_RX_DP[3:0] DMI2 Receive Data Input
DMI_TX_DP[3:0]
DMI_TX_DN[3:0] DMI2 Transmit Data Output

Table 6-8. Intel QPI Port 0 and 1 Signals

Signal Name Description
QPI{0/1}_CLKRX_DN/DP Reference Clock Differential Input. These pins provide the PLL
reference clock differential input. The Intel QPI forward clock
frequency is half the Intel QPI data rate.
QPI{0/1}_CLKTX_DN/DP Reference Clock Differential Output. These pins provide the PLL
reference clock differential input. The Intel QPI forward clock
frequency is half the Intel QPI data rate.
QPI{0/1}_DRX_DN/DP[19:00] Intel QPI Receive data input.
QPI{0/1}_DTX_DN/DP[19:00] Intel QPI Transmit data output.

Table 6-9. Intel QPI Miscellaneous Signals

Signal Name Description
QPI_RBIAS This input is used to control Intel QPI bias currents. QPI_RBIAS is
required to be connected as if the link is being used even when
Intel QPI is not used. Refer to the appropriate Platform Design
Guide (PDG) for further details.
QPI_RBIAS_SENSE Provides dedicated bias resistor sensing to minimize the voltage
drop caused by packaging and platform effects.
QPI_RBIAS_SENSE is required to be connected as if the link is
being used even when Intel QPI is not used. Refer to the
appropriate Platform Design Guide (PDG) for further details.
QPI_VREF_CAP Intel QPI voltage reference used to measure the actual output
voltage and comparing it to the assumed voltage. Refer to the
appropriate Platform Design Guide (PDG) for further details.