GPT Partitioned Disk not Recognized by BIOS

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Are you sure you have setup the Bios to operate as UEFI only ? (Without legacy/CSM support.)
I've seen a couple of Bios variants that wouldn't accept GPT disks for UEFI boot if the legacy support was also on.

The logic seems to be based on the incorrect assumption that if you have legacy enabled your OS isn't UEFI capable and therefore also is MBR boot only. So the Bios doesn't even attempt to boot from the GPT/UEFI harddrive.

Weird thing is that those same Bios often do boot from an GPT/UEFI external media if you manually select that as boot-device. Makes no sense whatsoever...

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tryptanethylamide
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tryptanethylamide

I love music, piano and computers. I live in Colorado, in the beautiful mountainous regions of Boulder and hopefully soon, Shambala (Crestone, CO).

Updated on September 18, 2022

Comments

  • tryptanethylamide
    tryptanethylamide over 1 year

    I have received a Samsung Ativ Book 4 (model no. NP4705E-K01UB [this computer is UEFI compatible BTW]), and for the first few months that I used it, it has worked fine with MBR partitioned disks.

    However, recently I installed OS X 10.9.1 as my secondary operating system, Linux being my primary; and naturally I knew that partitioning the disk as GPT would be required. Anyway, that's no problem. So I back up my data and partition my HDD as GPT, 3 partitions altogether, and I successfully install Mavericks. Great.

    Unfortunately, when I reboot after the install I get an error message stating that all boot options have been tried and to restart the computer.

    Looking in the BIOS I am surprised to see that my hard drive is not only not listed as a bootable drive, but it ISN'T FOUND AT ALL! My BIOS does not see it internally. Doing further tests, I took out the HDD and connected it via external USB 3.0 connection and the hard drive is recognized just fine! So it seems my BIOS refuses to read the GPT disk internally for whatever reason.

    Is there anyone who could shed some light unto why this peculiar problem only is relevant when the disk is connected internally and non-existent when connected via USB? Is there a solution to this problem? I have a temporary fix at the moment, having installed a EFI boot-loader called Clover onto a 1GB flash disk; I must use this Flash Drive to boot up into my HDD every time. Rather annoying. Appreciate any of the help I can get!

    Here's some pictures of my BIOS:

    enter image description here

    enter image description here

    Boot List: Kingston DataTraveler is the Flashdisk I mentioned earlier:

    • Ramhound
      Ramhound about 8 years
      Can you mount the EFI partition and post a screenshot of its contents? How you mount the EFI partition in Windows is well documented.
    • Daniel B
      Daniel B about 8 years
      The only screenshots you have provided are from boot-related pages. Please look for SATA settings and see if it’s listed there.
    • tryptanethylamide
      tryptanethylamide about 8 years
      I've uploaded a photo of the SATA settings.
  • tryptanethylamide
    tryptanethylamide about 8 years
    Hello, thanks for taking the time to answer! Yes I am sure to have set the BIOS for UEFI OS only, having just checked and confirmed. Also, another interesting thing I noticed, was that my HDD (a Toshiba) is recognized on the first page of the BIOS as the SATA 1 port, however there are no boot options for it still. Would changing the AHCI settings have any effect?
  • Tonny
    Tonny about 8 years
    Maybe if it currently isn't set to ahci. (Legacy or ahci/raid could be problematic.)
  • tryptanethylamide
    tryptanethylamide about 8 years
    AHCI was on manual and enabled, and I've switched it to automatic with no noticeable difference. I've tried switching the CSM or UEFI to both ON and this made no noticeable difference either.
  • Tonny
    Tonny about 8 years
    Mmmhh.. Very strange. I'm all out of ideas at this point.
  • Admin
    Admin about 8 years
    So when you boot off a flashdisk, you are actually running the hard drive from the internal laptop SATA port? I don't understand how you are able to boot off the hard drive if your BIOS is not recognizing it.
  • tryptanethylamide
    tryptanethylamide about 8 years
    Looking back at my BIOS, it DOES recognize the hard drive as a SATA port, however it doesn't recognize it as a boot device for some strange reason. On the first page of the BIOS it lists my HDD as the SATA 1 port, but only lists the flash drive as a boot device, as it has no problems booting GPT externally. When the disk was MBR it was a viable boot device but disappears when partition changes to GPT..