AGP, PCI-1, PCI-2, PCI-3, PCI-4, PCI-5 and LAN dividedly used an IRQ.

Manually assigning the IRQs is possible in BIOS "PnP/PCI configuration" submenu,
PIRQ_0 is for AGP
PIRQ_1 is for PCI-1
PIRQ_2 is for PCI-2
PIRQ_3 is for LAN
PIRQ_4 is for PCI-3
PIRQ_5 is for PCI-4
PIRQ_6 is for PCI-5
PIRQ_7 is for reserve