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Where are my Megabytes?

527 Views 5 Replies Latest reply: Apr 16, 2012 10:25 AM by Gary - former developer RSS
Gary - former developer Level 1 Level 1 (95 points)
Currently Being Moderated
Apr 15, 2012 10:24 AM

I have an external firewire hard drive case and 2 identical Maxtor 300 GB disks. If I install the first disk into the case it mounts with all 300 GBs available for use.


But when I put the other disk into the case, it mounts with only 128 GBs as its maximum capacity.


I have several hard disk tools but none of them has the ability to give me the full capacity of the drive.


What product can give me acces to the full capacity of the drive?




G4, Mac OS 9.2.x
  • Texas Mac Man Level 8 Level 8 (44,210 points)
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    Apr 15, 2012 11:50 AM (in response to Gary - former developer)

    OS 9 can utilize/"see" 128GB max.


     Cheers, Tom

  • Don Archibald Level 10 Level 10 (101,125 points)
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    Apr 15, 2012 12:18 PM (in response to Gary - former developer)

    The 128GB limit shold apply only to hard drives on the internal IDE/ATA bus, and is applicable to original QS and earlier G4s, as well as G3s, etc.; it is not applicable to QS 2002 G4s and later. It is a limitation of the built-in IDE/ATA controller, not of the OS, and should not affect drives connected via firwire drive (nor USB drives, for that matter).




    If that drive had ever been used and formatted on a machine subject to the limitation as an internal drive, it could well have been formatted as limited to 128GB. This should be able to be undone by reformatting (re-initializing) the drive.


    Note, though, that OS 9's Drive Setup can not reformat a firewire drive. However, such can be done using Disk Utility on a machine running OS X. If that is done, be sure to select the option to install OS 9 drivers, and to choose Mac OS Extended (not journaled) as the format. Further note - this might be easiest of the OS X machine is running OS X 10.4 or earlier.

  • Jeff Level 6 Level 6 (11,160 points)
    Currently Being Moderated
    Apr 15, 2012 8:00 PM (in response to Gary - former developer)

    The question that Don raised was whether one of your Maxtor 300 GB drives had been formatted when installed on the internal IDE bus, in a Mac that doesn't support large drives (128 GBs->).  If this was the case, it would still appear as a 128 GB drive when installed in the FireWire enclosure, in spite of the fact that FireWire-connected drives don't have that limitation.  If you connected that FireWire housing and drive to a Mac that's running OS X or booted to the Mac OS X installer disk, you could use Disk Utility to reformat the drive to its full capacity.


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