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Apple recently replaced our MacBook hard drive and we then loaded a bunch of our media, data and apps back on to the new drive. It was restored to the original OS 10.4.
Yesterday we finally bought Leopard but it is asking for us to reformat the drive to GUID. I've never ever been asked to reformat on an OS upgrade. The Apple Store is now taking care of backing up our data and reformatting the drive but they can not explain what GUID is and why the drive needs it. I looked on the web and I am even more confused.
My question is, why and how did Apple install a new drive without GUID in the first place if GUID is needed?
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Why they installed it that way, I can't tell you. Leopard on Intel requires a boot drive to be formatted in the GUID format. It will read a partition formatted in the old APM format, but it won't boot from it. From my understanding of GUID (which is that the EFI requires it to be GUID in order to boot), I would have thought Tiger would have required it to be that way too.
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MacIntels are able to boot from APM, they don't require GUID.
But firmware updates can go awry.
Proof you say?
The Leopard install DVD is APM format, not GUID.
Also, my numerous posts with links that back up this info.
BGnR
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What BGnR said. This came up during a firmware update last year (September). You'll be able to boot from an APM drive but you'll get hosed down the road if a firmware update comes your way.
I got around it by booting from my SuperDuper clone, reformatting my internal MBP drive, and then cloning back. Then ran the firmware updater afterwards with no problems.
A few threads from over @ Apple discussion re/the subject. Note that, at the time of posting, I wasn't (apparently) aware of the non-issue with booting from APM as a general rule.
http://discussions.apple.com/thread.jspa...ID=5457590�
http://discussions.apple.com/thread.jspa...ID=5457510�
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well, I know for a fact that you won't be able to install Bootcamp on a non-GUID formatted drive.
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[quote rz]well, I know for a fact that you won't be able to install Bootcamp on a non-GUID formatted drive.
I have.
BGnR
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So if I am understanding this, Apple should have formatted the drive with GUID.
Since this is all new to me, where do we look to see that a drive is formatted GUID or not?
I checked Disk Utility and I didn't see GUID in the description of my G5 hard drives.
Where do you select GUID in the formatting options and is the choice just between GUID and APM ?
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[quote loveshine]So if I am understanding this, Apple should have formatted the drive with GUID.
Since this is all new to me, where do we look to see that a drive is formatted GUID or not?
I checked Disk Utility and I didn't see GUID in the description of my G5 hard drives.
Where do you select GUID in the formatting options and is the choice just between GUID and APM ?
In Disk Utility.
Click on the on the HDD, the one that is on top.
On the bottom of the window a "Disk Description" will appear with a bunch of info including "Partition Scheme."
The "Help Menu" describes this in detail.
BGnR
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[quote BigGuynRusty][quote rz]well, I know for a fact that you won't be able to install Bootcamp on a non-GUID formatted drive.
I have.
BGnR
really? I tried running the Bootcamp Assistant in Leopard with an APM formatted drive, and it wouldn't even run.
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[quote rz][quote BigGuynRusty][quote rz]well, I know for a fact that you won't be able to install Bootcamp on a non-GUID formatted drive.
I have.
BGnR
really? I tried running the Bootcamp Assistant in Leopard with an APM formatted drive, and it wouldn't even run.
I should have been clearer.
During the development period, before the MacIntel was fully developed, Apple was considering using APM instead of GUID, and we could use either format to test BootCamp, among other things.
That was the time Apple decided to leave OpenFirmWare and move to EFI.
BGnR
