Great info, you guys.
I've been looking a PC specifications, based upon the tips given here.
As advised, there seems to be provision of an IDE connection inside SATA machines. I think I'd disconnect the SATA drive to ensure no problems with my ATA caddied drives. SATA speeds are irrelevant for what I do on the PC.
Maybe a silly question, but I'll repeat that I'm just a computer novice ---What the PC suppliers don't make clear is whether the IDE connection is taken up by an existing device in their particular machine. Unhelpful (and costly) advice lines and undertrained staff aren't providing answers. Is this a possible problem, or can the IDE slot only ever be occupied by an ATA hard drive? I'd be miffed to receive a new PC only to find that the IDE cable was already connected to something vital.