Pci Interrupt Request Routing - MSI KT4 Ultra User Manual

KT3 Ultra2-C ATX Mainboard
KT4 Ultra ATX Mainboard

PCI Interrupt Request Routing

The IRQ, acronym of interrupt request line and pronounced I-R-Q, are
hardware lines over which devices can send interrupt signals to the
microprocessor. The PCI IRQ pins are typically connected to the PCI bus INT
A# ~ INT D# pins as follows:
PCI Slot 1
PCI Slot 2
PCI Slot 3
PCI Slot 4
PCI Slot 5
PCI Slot 6
2-32
Order 1 Order 2
INT A# INT B#
INT B# INT C#
INT D# INT A#
INT C# INT D#
INT B# INT C#
INT C# INT D#
Order 3 Order 4
INT C# INT D#
INT D# INT A#
INT B# INT C#
INT A# INT B#
INT D# INT A#
INT A# INT B#