Macintosh: Using 128 GB or Larger ATA Hard Drives

Not all Macintosh products can take advantage of the full capacity of large (128 GB or greater) hard drives that use 48-bit LBA when they are connected via an ATA controller. Other controllers (SCSI or FireWire) are not affected.

There are two primary requirements that must be met for higher capacity hard drives to be fully utilized within a computer.

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Mac OS X 10.2 or later

The high capacity drive must be formatted using Mac OS X 10.2 or later in order for partition sizes beyond 128 GB to be recognized. If you plan to start the partition up from Mac OS 9.2.2, the partition sizes may be a maximum of 200 GB. If you have a drive that is larger than 200 GB in size, you will need to create multiple partitions with no single partition exceeding 200 GB in size. Once formatted, the drive will be recognized under the version of Mac OS 9.2.2 that comes with the Power Mac G4 (Mirrored Drive Doors) and later products.

If the drive is not formatted using Mac OS X 10.2 or later, the maximum volume size available is limited to approximately 128 GB.

Support via the BootROM

The BootROM of Power Mac G4 (Mirrored Drive Doors), Xserve, Power Mac G5, and any other model introduced after June 2002 can accommodate these larger drives.
For additional details on the volume and file size limitations under OS X, see:

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