GUID or Master Boot Record?

[JoyMODE101]

hey everyone

i have my external hd formatted as master boot record and is works fine on intel macs, ppc's, and windows (vista)

i'm going to reformat my actual macbook pro's hd with leopard,
and i know that the default is GUID, but what would happen if i formatted
it as Master Boot Record?

would it work?
and... if it does work, is there a benefit to using that scheme instead of GUID??

thanks everyone

[systemexclusive]

... and i know that the default is GUID, but what would happen if i formatted it as Master Boot Record?

It is just a partition table, just 64 LBA. Don't waste your time .
On my side internal drive have a GUID partition table, all external drives has Master Boot Record partition table (because they can be plugged into other system such as PC)...

[JoyMODE101]

Originally Posted by systemexclusive

It is just a partition table, just 64 LBA. Don't waste your time

thanx system

but, what's 64 LBA for?
any good info on it?

i googled it and just got too much [bleep][bleep][bleep][bleep] lol
how does it pertain to intel macs?

[jhamrick]

Master Boot Record is AKA FAT32, which is a PC format that the Mac can also read. Most combo drives (PC and Mac Compatible) use Fat32 file system. There is only one gotcha with FAT32 and that is you can't copy, to the drive, a file that is larger than 4GB - it's a limitation of the file system. Not usually an issue until you get into doing Video. Also, you will run into this limitation if you want to create a disk image(backup) of your hard drive (using apple disk utility). The image file will be too large to copy to FAT32. And last but not least, I would not recommend partitioning your internal Mac volume using FAT32, leave it GUID and formatted as Mac OS Extended or Mac OS Extended(Journaled) - There is no 4GB file limit with these formats.

-Hope that makes sense.

[systemexclusive]

Originally Posted by jhamrick

..Master Boot Record is AKA FAT32...

Master Boot Record - is a way to declare partitions on drive.
Master Boot Record has no any file-size limitations. It is lets say "Header" of hard drive, but it is not affect concrete file of directory.

You can see MBR or GUID by yourself http://www.macupdate.com/info.php/id/30217/ibored or http://apps.tempel.org/iBored/ and compare what you see to article from Wiki http://en.wikipedia.org/wiki/Master_boot_record

[jhamrick]

I stand corrected my definition is not accurate. With that being said my point is the same, there is a limitation with FAT32 (file system) that doesn't allow you to copy, to the drive, files larger than 4GB in size. Most external drives you purchase that are both PC and Mac compatible use an MBR partition table and a FAT32 formatted file system.

In fact i would be curious if you could even create a MBR partition table and format the drive Mac OS Extended, I have not tried nor would I waste my time. My initial thought would be no.

[systemexclusive]

Originally Posted by jhamrick

... In fact i would be curious if you could even create a MBR partition table and format the drive Mac OS Extended, I have not tried nor would I waste my time. My initial thought would be no.

Agree. GUID partition scheme used by default on Mac.
I have Mac OSX Extended partition under MBR partition table. But it is an exception from rules: http://farm3.static.flickr.com/2674/...ea83c3bd_o.png

[kennai]

Hello all. I have recently carbon copy cloned and made bootable a new SATA drive. My source disk was GUID, and now I see that my clone is APM ( apple Partition Map). When I go to open PTs on the clone, I get a screen that says PTs quit unexpectedly, and I have the option to send the info to Avid. All of my other drives are GUID. My question is , why did my "clone" drive become an APM partitioned drive? Is there a preference somewhere in Carbon Copy Cloner that I missed?
Thanks in advance,
Kenneth