Aaeon PCM-5890 Manual page 60

This sets the method by which the PCI bus recognizes that an IRQ
service is being requested by a device. Under all circumstances,
you should retain the default configuration unless advised
otherwise by your system manufacturer.
Choices are Level and Edge.
This allows you to configure your system to the type of IDE disk
controller in use. The more apparent difference is the type of
slot being used.
If you have equipped your system with a PCI controller, changing
this allows you to specify which slot has the controller and which
PCI interrupt (A, B, C or D) is associated with the connected hard
drives.
Remember that this setting refers to the hard disk drive itself,
rather that individual partitions. Since each IDE controller
supports two separate hard drives, you can select the INT# for
each. Again, you will note that the primary has a lower interrupt
than the secondary.
Selecting PCI Auto allows the system to automatically determine
how your IDE disk system is configured.
Refer to the above description .
Chapter 4 Award BIOS Setup 51
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