Info on external HDD's please

[jenonnet]

Hi
Please can someone give me some info on external hard disc drives.
Is it possible to change an internal HDD to an external one? I have seen HDD cases for sale with a USB lead & other stuff. Is this what you get to change an internal one to an external one? If so, how do I know which one to get as there are lots of different ones?
I have got a spare HDD in my old PC which I would like to change into an external portable one to use with my new PC & laptop, if possible, as that seems to be a cheaper option than having to buy a new external HDD (they're expensive!) So if I get the HDD case & kit can I change my internal one to an external portable USB one?
Any info on this would be greatly appreciated, thanks.

[silver]

not sure what you call 'expensive' - you can get a really good size external harddrive for ~50 quid or less

how big (storage capacity / gigs) is the harddrive in the old PC,. it's likely to be pretty small (if it's old) plus it may not have that much life left in in,.

[bouncingjohn]

Yes, it's perfectly possible. You need to know three things before choosing a caddy:

i) the type of drive you have - IDE or SATA. IDE drives are the ones that are connected via a 80-wire ribbon cable. SATA are connected via a thin, usually red, cable.

ii) the physical size of the drive (3.5" or 2.5".)

iii) the amount of data the drive can hold (some caddies restrict you to a maximum).

Then it's just a case of matching up the available caddies with the HDD you're going to put into it.

You might also want to consider how you want to connect to it: most will be via USB, but if you have a SATA drive you might also be able to connect via eSATA.

*edit* Sil beat me to a reply, but his comments are fair re size/life left.

[jenonnet]

Thanks so much for your replies. The hard drive I have in my other PC is 80gb & is about 3 or 4 years old. I used it to save all my data to instead of using the same drive the system files were on. Unfortunately the computer died & wouldn't even boot up, not even from the Windows set up disc, so I've treated myself to a new PC. Problem is, there's still data on the second drive that I could do with getting off, so I thought I'd kill two birds with one stone & find out if I could turn it into an external drive connected by USB. If this was possible it would also mean I could retrieve my data.
Thanks to you both I now know I can, so it looks as if I'm going to be taking the old PC apart to get at the drive. Don't you jusst love these learning curves?!! lol
Thanks again.