Ask Different is a question and answer site for power users of Apple hardware and software. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

Is it in principle possible to swipe the hard disk out of a MacBook, swipe a new (blank) hard disk in, install the OS on the new disk, then swipe the old disk back in and find the machine operational again?

I would like to tinker with a new hard disk (bootcamp and perhaps rEFIt), but if that fails, I'd like to continue from the installation I have right now.

Edit Clearly, the hard disk will be unchanged. My question is whether the process of installing OS X / bootcamp will change something (SMC, PRAM, ...?) that makes the machine incompatible with the previous installation.

share|improve this question

Yes, certainly. Removing the original drive will leave it exactly as it was before.

share|improve this answer
It's clear that nothing can change on the hard disk while it's disconnected. I have now clarified the question. – Calaf Oct 15 '12 at 14:41
I know a guy whose double boot was in fact a double drive. One for Windows, one for the Mac OS. Worked perfectly. – Matthieu Riegler Oct 15 '12 at 16:41
@MatthieuRiegler Did this involve removing the internal drive every time, or could he reboot into the other OS without using a screwdriver (a KVM-style switch for SATA perhaps..?) ? – Calaf Oct 17 '12 at 17:20
Nope. He needed to remove 2 screws (Old Macbook) to change the HD. So it's not a very convinient solution but I works. – Matthieu Riegler Oct 17 '12 at 21:03

On the first boot after changing a drive it may take an extra couple of seconds for the new boot destination to be written to the PRAM, but it won't cause any issues.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.