MSI K8MM2 Manual page 56

IRQ 3/4/5/7/9/10/11/14/15
These items specify the bus where the specified IRQ line is used.
The settings determine if AMIBIOS should remove an IRQ from the pool of available
IRQs passed to devices that are configurable by the system BIOS. The available IRQ
pool is determined by reading the ESCD NVRAM. If more IRQs must be removed from
the IRQ pool, the end user can use these settings to reserve the IRQ by assigning an
[Reserved] setting to it. Onboard I/O is configured by AMIBIOS. All IRQs used by
onboard I/O are configured as [Available]. If all IRQs are set to [Reserved], and IRQ
14/15 are allocated to the onboard PCI IDE, IRQ 9 will still be available for PCI and PnP
devices. Available settings: [Reserved] and [Available].
MSI Reminds You...
IRQ (Interrupt Request) lines are system resources allocated to I/O
devices. When an I/O device needs to gain attention of the operating
system, it signals this by causing an IRQ to occur. After receiving the
signal, when the operating system is ready, the system will interrupt itself
and perform the service required by the I/O device.
BIOS Setup
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