Taking a few minutes to go read the Wikipedia article on SCSI won't be a bad idea.
The "primary" and "secondary" are referring to the IDE controllers. You're not going to get SCSI disks to show up there.
It sounds like you've got fixed-mounted drives rather than hot-plug. If I'm wrong then this needs to be edited.
That machine has an integral SCSI controller on the motherboard. Its the LSI Logic controller that you see bannering its ROM messages directly below the errors about the primary and secondary IDE disks not being recognized in your screenshot. I'm fairly certain that DBAN will support the LSI Logic controller (w/ a Symbios Logic driver), whereas I'm not certain it will support the PERC. With that in mind, I'd ditch the PERC and use the motherboard controller.
Each disk should have a 68-pin female connection. There should be a cable with multiple male connectors to attach the disks to the controller. There is a 68-pin female connector on the motherboard for the integral SCSI controller (near the IDE connectors).
In a fixed-mounted configuration each disk has a jumper block to set the unique device ID. The disks should still be jumpered for unique IDs (so don't play w/ the jumpers). The last device connected to either end of a a SCSI bus must be a terminator. The motherboard SCSI controller will have an integral terminator. Not all hard disk drives can act as terminators, so your cable may have a terminator either integrated after the last female socket or attached to the last female socket. If the drives are capable of acting as a terminator then one of them will be jumpered for termination and should be connected last on the chain. (Post the drive model number in your question and we can link you up to the docs.)
Once you've got the drives connected to the motherboard controller you should see them detected by the controller.
Edit:
Perfect. You have an integral terminator on the cable. The disks should already be jumpered w/ unique IDs (don't move any jumpers now) since this was a working configuration.
With one disk attached to the SCSI cable and the cable attached to the motherboard SCSI connector (just as you showed in your photo) you should be able to see the disk detected by the LSI Logic SCSI controller during POST.
It's unclear to me if the disks were originally connected to the PERC or the LSI controller. I suppose it's possible, since the LSI is configured for ID 5 that one of the disks is also configured for ID 5 (the ID for each device, including the controller, must be unique on the SCSI bus), which would cause problems (typically showing no devices detected on the chain except the controller). If you find that one of the disks doesn't detect then, likely, you've got an ID conflict with that disk. You can always pull the ID jumpers completely, which will ID the disk as zero.
So, it's solved.
In the main bios, in startup options, pci device boot priority was set to Planar SCSI. I set it to Slot1, and rebooted. I then set it back to Planar SCSI, and at the next reboot it found the hdd and windows 2003 started normally. Whew!
Best Answer
No, a SCSI controller and a RAID controller are different, although some SCSI controllers can have basic RAID functionality. Raw Ultra 160 SCSI drives were phased-out beginning in 2002. Are you dealing with an extremely old system?
Generally, there are a few terms to explain.
SCSI is a protocol, but can also describe type of drives. Your mention of Ultra 160 describes a generation of parallel SCSI technology.
Since SCSI is a protocol, you can have single SCSI disks or other devices like tape drives that communicate via SCSI. Typically, the interface will be a SCSI controller/adapter.
RAID controllers add RAID logic, caching and logic to this equation...
But I'm just speculating on your setup. please provide more details about your server equipment.