Configure each SCSI device to have a unique SCSI ID, and on the adapter's Advanced Configuration Options setup menu, set the Plug N Play SCAM Support option to Disabled.
Using the Adaptec configuration utility:
If there is more than one controller (or an embedded controller), try to use one IRQ per controller.
Enable bus mastering for the slot(s) with your host bus adapter(s), when the choice is given.
For older disk drives, tape drives, and most CD-ROM devices, make sure the maximum SCSI data transfer speed is set to 5.0 Mbps.
Enable support for disks larger than 1 Gbyte if applicable.