Originally Posted by toonpornblog

SCSI. Always. To put it (not 100% nerd correct, but good enough to be considered truth) as simply as possible, with IDE, your CPU handles all of the transactions, and you can only do one at a time. With SCSI, this is offloaded to the SCSI controller, so the CPU is free, and you don't have it 'waiting' while it's locked in one task, before you can go on to another.

If you do a load of photo work (as you mentioned above), go SCSI. U320 isn't that expensive. The disks are, and they're a bit smaller, but put your OS on one, and use another SCSI disk for your scratch/etc, and maybe just an SATA for 'big storage'. You'll be glad you did.