Is the SCSI motherboard one which also includes IDE interface? If not you will need to get an IDE controller. I would think if your motherboard has onboard SCSI then it should have boot to SCSI if you intend on having SCSI as your boot drive. If you have an IDE motherboard with a SCSI adaptor, and the IDE interface is an ATA66/100 controller, then you will not be able to boot to the SCSI unless you can disable the ATA controller or dont have a bootable OS on the drive that is on the IDE interface, as the onboard IDE controller will have boot priortiy because an ATA66/100 controller is also SEEN as a SCSI device.