Onboard LAN Boot ROM [Disabled]

This field allows you to enable or disable the option ROM in the onboard LAN chipset. Configuration options: [Disabled] [Enabled]]

Onboard ATA Device First [Yes]

This field allows you to select the onboard ATA or a SCSI device. The default setting [Yes] selects the onboard ATA device. Selecting the option [No] selects the SCSI device. Configuration options: [No] [Yes]] PCI IRQ Resource Exclusion

IRQ XX Reserved [No/ICU]

These fields indicate whether or not the displayed IRQ for each field is being used by a legacy (non-PnP) ISA card. The setting [No/ICU] for an IRQ field indicates that you are using the ISA Configuration Utility (ICU), and that this particular IRQ is NOT required by a legacy ISA card. Set the IRQ field to [Yes] if you install a legacy ISA card that requires a unique IRQ and you are NOT using ICU. Configuration options: [No/ICU] [Yes]

ASUS P4B-E motherboard user guide