Finx,
SCSI is one thing I do know a lot about.
My server is using a SCSI array. SCSI has a few advantages over IDE.
Depending on the which type you get it can support between 7 & 15 devices off a single port. Unlike IDE, SCSI uses very little processing time to do reads or writes.
SCSI adapters & nearly all devices made in the last 5 years support what is call 'disconnection'. What this means is say you have 3 HD's on a single SCSI chain & connect a activity LED to each one. Then pump large files to each drive at the same time you will see that all the drive led's seem to be on at the same time. What is happening is that the SCSI controller issues a command to each drive & then 'disconnects' enabling it to send a command to another drive, and so on. when the drive has completed the task it sends a ready signal to the controller which reconnects and sends more data or whatever.
Unlike IDE - SCSI has alot more standards/interfaces. It also supports external devices, My server is running 6*9.1GB drives (RAID 5) using a RAID controller. On another SCSI controller I've got 2 internal CDROMS & and a external DLT 35/70 tape drive.
It's usually cheaper to get a SCSI controller on a PCI card than to get one built onto a Mobo.
Raid 0, 1 and 0+1 on IDE are the same as they are for SCSI. SCSI RAID controllers also offer RAID 5 which is a compromise between RAID 0 & 0+1.
SCSI Controllers & SCSI RAID controllers are not the same thing - there is a huge cost difference. As there is between anything SCSI & IDE. SCSI devices have a lot more intelligence on board than IDE drives.
Sorry if I've rambled on, this is quite a complex topic.
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