I haven't seen USB to SAT/IDE cables separate from the external enclosures, although I won't dispute that they might exist.

I've used several external USB enclosures, with a couple that took an IDE drive only, one that took an SAT only, and about three that will take either kind of drive, using one or the other set of connections inside.

If you put it in one of the typical boxes (or if your cable does the same thing) the hard drive card/connection in the computer doesn't see the hard drive. The USB connection feeds directly through the USB port on the computer, but is named like a hard drive, even though the computer doesn't really see it like one.

Since the hard drive in the external box (or hooked to the cable) is "primary" to the USB port it hooks to, the usual setting for the drive is as primary, not as slave.

Most of the External USB cases use a wall wart (plugged into AC power) and don't take their power from the USB port they're connected to, so with those cases there shouldn't be a problem with having enough poop to spin any drive you can put int them. Trying to take enough power from a USB port might be problematical.

Without recommending a seller, since Best Buy is the only one in my town, you might want to take a look at Enclosures generally, or the closest equivalent to a couple I have. (Ones I've used were "Monster" label, from CompUSA that I believe were marketed from Canada, but CompUSA left town, so Best Buy is the only place I've got to look at stuff now. (Sympathy acknowledged.)

All the cases I've looked at have an external transformer (wall wart) that plugs into AC power to spin the drive so getting enough poop to run any drive shouldn't be a problem. Trying to pull enough power out of a USB port alone could be a problem(????) but I haven't really looked at the spin moter draw on any typical ones.

The master and slave jumper settings on the hard drive are so that the IDE or SAT port can tell which drive it's talking to. If the HD is in a USB box, the USB port takes care of the identity, and so as far as I've seen any HD in a USB box, or otherwise going through a USB port, should be set to the master jumper position. There could be exceptions, but I haven't seen any. Connecting to a HD via USB is more like connecting to a HD on another computer via a LAN than to plugging into a HD port in the computer. (A rather crude simile, but it might help how you think about the situation???)

I've pretty much given up on the USB cases for any general use, since the rather rapid expansion in HD space needed means that any HD old enough to come out of something is probably too small to be very helpful as an auxiliary (external or otherwise) drive, but having a case you can test out a drive with, or that you can hook up to get stuff off of one is pretty handy, so I keep a couple of the AT/SAT type handy. For testing purposes, you don't have to close the case, but you can be pretty sure the front end will take care of the signals and power.

As an almost incidental, I've seen some indication that the external USB HD cases I've used are a little lacking in heat dissipation, so an internal HD stuffed in one may have a slightly shorter life than you could expect with the same drive inside a computer - assuming the computer case has fair air circulation inside. The difference I've seen isn't something I can confirm; but evidence has been enough to raise a suspicion in my own pitiful little brain.

(I replaced an internal HD that's been running external in a USB box a few days ago, possibly due to overheating(?) in the box, with a "real portable USB external drive," with the result that Western Digital is on my piss list this week, but that's another story.)

John