changing partition map scheme

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Level 3

534 points

changing partition map scheme

I want to create a bootable partition on an external FW drive. I checked in the Disk Utility, and it says the Partition Map Scheme is Apple Partition Map, and I know it needs to be GUID to be able to install Leopard. Where can I change this scheme? I don't see any option to do so in DU.

I do have the data backed up, so I can reformat if necessary. Thanks.

Mac Pro, 8-core 2.8 Ghz, 6 GB RAM, Mac OS X (10.5.6), Logic 7.2.3, Mountain Dew

Posted on Mar 16, 2009 2:14 PM

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Answer 1

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nerowolfe

Level 6

13,090 points

Mar 16, 2009 2:19 PM in response to jdredge

You will find the partition scheme only when you select the actual drive (not a partition) in DU.
Partition Map Scheme is listed at the bottom.
You need to reformat and repartition the entire disk to be able to change the PMS since it applies to the entire disk structure, not just a single partition.
I believe if you select the drive and then select partition you have the option to select the scheme.
You may have to also erase the drive in order to have the option.

Message was edited by: nerowolfe

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Answer 2

Mar 16, 2009 2:24 PM in response to jdredge

jdredge,

Leopard has nothing to do with the need for GUID or APM; it can be installed on either. Intel Macs require GUID, PPC Macs APM. That's the reason to use one or the other.

In Disk Utility, you must select the drive, not a named volume that will appear indented below the drive. Once you have selected the drive, click the "Options..." button in the Partition pane (not the erase pane). Repartition the drive using the same single-volume scheme.

Scott

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Answer 3

Jaunty

Level 1

9 points

Mar 23, 2009 7:31 PM in response to jdredge

I am reformatting a 500Gb WD Passport in Disk Utility before trying to stick it in my Macbook and found this thread.

For the benefit of others, you need to go in to the Partition section and where it says Current change that to 1. This will then let you select Options where you can change the Partition Map Scheme to a GUID Partition Table so you can have a bootable drive for Intel Macs. Presumably if you want more partitions you can then add them.

Cheers.

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Answer 4

jdredge Author

Level 3

534 points

Mar 16, 2009 2:41 PM in response to Scott Radloff

Scott Radloff wrote:
Intel Macs require GUID, PPC Macs APM. That's the reason to use one or the other.

Yes, I was aware of that, I simply meant that in this case I couldn't install Leopard on the drive (because I'm using an Intel Mac).

In Disk Utility, you must select the drive, not a named volume that will appear indented below the drive. Once you have selected the drive, click the "Options..." button in the Partition pane (not the erase pane). Repartition the drive using the same single-volume scheme.

The options button is grayed out. I think I need to do the reformat first, as nerowolfe suggested.

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Answer 5

jdredge Author

Level 3

534 points

Mar 16, 2009 2:42 PM in response to nerowolfe

Thanks, I'll check into that.

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