Why is different info displaying in Disk Utility for Toshiba X300 4TB

Discussion in 'Mac Pro' started by sngraphics, Dec 24, 2016.

  1. sngraphics macrumors member

    Aug 27, 2010
    Just installed a Toshiba X300 4TB in my MacPro.
    Partitioned and erased in Apple's Disk Utility.

    Why does it display different info (at the bottom) for this drive as compared to my other 3 drives?

    Why the difference in the info that is displayed?
    Is anything wrong with these Toshiba drives or is that normal?

    Toshiba X300 4TB vs Seagate.png
  2. h9826790 macrumors G4


    Apr 3, 2014
    Hong Kong
    Are you sure that's a 4TB HDD? Did you check the label on the HDD.
  3. ActionableMango macrumors G3


    Sep 21, 2010
  4. filmak macrumors 65816

    Jun 21, 2012
    between earth and heaven
  5. sngraphics thread starter macrumors member

    Aug 27, 2010

    Yes. This is a 4TB HD.
    --- Post Merged, Dec 30, 2016 ---

    Thank you for the reply. Good info.
    But I did have one strange thing happen while working with these drives.
    (I have two of these)
    I have one installed internal in MacPro and have one attached external via USB 3.0.
    When I erased the external with Disk Utility all of a sudden the correct info appeared at the bottom.

    Why would the correct info show up in Disk Utility when attached external and not show up when attached internal?

    Also I have SoftRaid Light installed.
    When I Initialize the internal disk using SoftRaid then open up Disk Utility it shows the correct info for the disk.
    Then when erasing again with Disk Utility the info returns to the screen shot on the left above in the first post.

    Any ideas, thoughts, info on this one would be greatly appreciated.

    Below is a screen shot of the external after erased in Disk Utility.

    Attached Files:

  6. curmudgeonette macrumors 6502

    Jan 28, 2016
    A vague theory: There's a drive size limit in the 2TB to 4TB range. This isn't a problem for drivers using newer IDE commands. However, drivers designed to an older standard can't access beyond the limit. Some 4TB drives I bought came with a little blurb mentioning special Windows software provided by the manufacturer to get around the limit. Nothing like that should be needed for Mac. Perhaps some software you have installed is splitting the drive into smaller segments?
  7. ActionableMango macrumors G3


    Sep 21, 2010
    I don't know, but it is not surprising that a bug would have inconsistencies.
  8. AidenShaw macrumors P6


    Feb 8, 2003
    The Peninsula
    For drives using the older "MS-DOS" partition table format, there's a hard limit of just under 2 TiB for the usable part of the drive. The partition table format can't express anything at 2 TiB or larger.

    The newer GPT partition table format has a much larger limit - therefore larger drives have to be formatted with GPT partitions to use more than 2 TiB of the capacity.

    The disk utility bug could be related to creating GPT partitions on larger drives.

    Earlier disks had a 128 GiB max size, due to 28-bit addressing. This was fixed with ATA-6 in 2003 to use 48-bit LBA addressing. ( https://en.wikipedia.org/wiki/Logical_block_addressing )

    The 2 TiB limit is most likely due to a disk formatting issue, and not a drive size limit.

    Note that a 2 TB disk is 1.819 TiB, so a 2 TB disk does not need GPT formatting.
  9. sngraphics thread starter macrumors member

    Aug 27, 2010

    Thanks for the info,
    But I still don't understand how Disk Utility formats this drive correctly when connected externally and not so correctly when installed internally.
  10. Weaselboy Moderator


    Staff Member

    Jan 23, 2005
    Two different drive controllers. Sounds like the controller in the external enclosure is able to handle this situation and the internal controller is not.

Share This Page