Hi John..Long time no speak <g> Nice to 'see' you again..I am still envious of your visit to Meigs some years ago (is it that long ?)
>>Will the device letters on the old system stay as they are, or will those following the D: drive (now removed) all move up by one?<<
I can't add much to Sams's excellent reply, except to say that your second HD (the one you wish to move over) is probably configured as a 'Primary Partition' (since it appears on your 'old' system as D:, and takes precedence over your other partitions above C:). In this case it will probably appear as the same drive D: on your new system.
As long as you're careful to make sure that the power is off (and in the case of newish motherboards this means that the power cable should really be unplugged at the rear before plugging in devices/cards, since these new boards do draw some power even when the system is off, and can be damaged) you shouldn't really have any problems. Some drives are also quite fussy over which IDE 40 way connector they use. You may have to try both your 'end' IDE connector (at the end of the ribbon cable, which is probably where your current HD is connected to) or the first one (further down the ribbon cable towards the Motherboard).
As long as your 'new' system is working normally when booting up from its current HD, your 'new' second HD shouldn't make any difference to the running, but it will move all your drive letters D: upwards as you suspect, since you are now displacing those letters with your new drive D:.
As Sam says, the data will not be affected, and you should be able to access it without problems, but any apps will need to be re-installed. Some apps read your bootable drive's MBR (Master Boot Record) or other records on your drive C: in order to check that they are on the same PC as the original installation. Others may not.
The program you use to access this data will also need to be redirected to the new location of the data, of course.
From your post, though, I suspect that you use this HD just for data. In that case, go for it !
If you do hit a problem, don't write anything to this drive until you sort it out. If all looks well, try writing a simple, expendable file to your new drive first, before risking any data.
Just yell if you have any problems.
Hope that helps.
Regards
Bill
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