• AGP and PCI-1 share an IRQ
• PCI-2 and PCI-3 share an IRQ
• PCI-4, PCI-6 share an IRQ
• PCI-5 and HPT 372 controller share an IRQ

Manually assigning the IRQs is possible in BIOS "PnP/PCI configuration" submenu,

• PIRQ_0 is for AGP and PCI-1
• PIRQ_1 is for PCI-3 and PCI-4
• PIRQ_2 is for PCI-5 and HPT 372 controllers.
• PIRQ_3 is for PCI-4, PCI-6