I have a question

[abibee]

When I get a new computer together, I'll be putting in an SSD for Windows/programmes, and using my current/old HD in the new computer as a secondary/data drive.
What I don't know is this. The SSD will become C: yes, so what will happen to the C: (and the XP installed in it) in my current HD when that's plugged in, will that need formatting or will it automatically become D:?
Sorry for the newbie question, the answer is probably simple, just I don't know it!

[kalniel]

Depends on the boot order in BIOS. If the SDD is listed as the first hard drive then you'll boot into Windows 7/8 and the old drive will be listed as D: and you'll see all the windows XP files still there.

If the HDD is listed as the first hard drive then you'll boot into XP and it'll moan at you for all the new hardware it's detecting.

[abibee]

That makes sense to me. Thanks.

[drone567]

You can simply change the boot order in the bios(google it).

[Willzzz]

Or just disconnect the old HDD entirely until you are all set up.

[abibee]

Yes, I know to set the order in BIOS, though it's been a while. I just wasn't sure what would happen to old C: after new C:.

[ik9000]

when you boot into XP on the HDD the HDD will be C: and the other drives (SSD etc) assigned a different letter

when you boot into win7/8 via the SSD then the SSD will show as C: and the other HDD assigned a different letter.

The drive letter is OS assigned and stored on the C: (ie the system drive) of whatever you're running at that time. It is not hard-coded into the drive as part of BIOS. BIOS sees the drive type and serial number, so the boot selection list will be something like

Samsung SSD
Seagate HDD
Optical Drive
USB drive

etc etc

You can manually change the drive letter assigned to things using "control panel ->all control panel items ->admin tools ->computer management->disk management " but again note this only changes the letter for whichever OS you are in at the time.

I have tried this on a dual boot system where the C: and K: in one install show up as E: and N: in the other install (the two OS are on different drives)

[cookie365]

Or just disconnect the old HDD entirely until you are all set up.

This.

[ik9000]

This.

You're not incorrect - it will be simplest to install the new OS on a clean drive without the other one connected to avoid potential confusion. However it doesn't actually help answer his question in the OP though, which is if he does disconnect it as you suggest, what happens when he then plugs it back in? Will he end up with two c: or will it break trying to work out which one is which, or will it call the HDD a different letter instead? The answer (as above) is the latter.

[abibee]

I think I'll err on the side of caution then, and install Windows 8.1 on the SSD, then once it's up and running then plug in the old HDD. Thanks.