Small warning for those wanting to 'try' Yosemite

Discussion in 'OS X Yosemite (10.10)' started by kwokaaron, Dec 7, 2014.

  1. kwokaaron, Dec 7, 2014
    Last edited: Dec 7, 2014

    kwokaaron macrumors 6502a

    kwokaaron

    Joined:
    Sep 20, 2013
    #1
    Although downgrading works if you don't like Yosemite, bear in mind that all new macs (all Haswell-based Macs, and Ivy Bridge rMBP 15" and 13") also get their EFI/SMC firmware upgraded as well. So downgrading back to Mavericks will make the startup screen when it chimes and the drive selection screen black instead of the white/grey...

    Edit: When I meant new, I meant 2012 onwards
     
  2. fisherking macrumors 603

    fisherking

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    Location:
    ny somewhere
    #2
    and the point is? the OS that comes with a new mac is the 'oldest' OS you should run on that mac. as is always the case...
     
  3. chrfr macrumors 604

    Joined:
    Jul 11, 2009
    #3
    The firmware update and black screen change applies at least to 2013 computers, which shipped with Mavericks.
     
  4. kwokaaron thread starter macrumors 6502a

    kwokaaron

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    Sep 20, 2013
    #4
    The earliest Mac (Ivy Bridge rMBP) that support this firmware change came with Lion. ;)

    What I meant was Macs that are comparatively new which doesn't have Yosemite preinstalled will have their firmware upgraded as part of the OS. While this isn't such a big deal itself, those that might downgrade it back to a previous OS will find the startup sequence inconsistent since the selection screen has changed into black while the loading of the OS (pre-yosemite) itself is grey.
     
  5. fotomarc macrumors regular

    fotomarc

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    May 8, 2014
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    Melbourne, Australia
    #5
    Why would you want to downgrade? I upgraded to Yosemite as soon as it came out and apart from a period of adjustment, it works fine!
     
  6. TPadden macrumors 6502a

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    Oct 28, 2010
    #6
    ..... because my toilet bowel swirls in an opposite direction! :eek:
     
  7. thejadedmonkey macrumors 604

    thejadedmonkey

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    Pennsylvania
    #7
    Have you looked at it?
     
  8. chrfr macrumors 604

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    Jul 11, 2009
    #8
    I don't have access one of those, but the 2012 11" Air I have did not get a firmware update with Yosemite, hence the "at least" in my response.
     
  9. Manic Harmonic macrumors 6502

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    Dec 4, 2011
    #9
    If you reboot twice after downgrading to Mavericks it should revert to white. It's not the firmware that changes the color, it's boot.efi. The boot.efi hack for the black boot screen on unsupported Macs changes the boot menu to black as well... The first time booting back into Mavericks, it's just a black screen, but after rebooting a few times it's white again. Then if you boot Yosemite again it takes a few reboots to return to black.
     
  10. mikecwest macrumors 6502a

    mikecwest

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    Jul 7, 2013
    #10
    Your toilet "bowel?" Well, after you flush the toilet, your bowel will no longer be inside the bowl.
     
  11. kwokaaron thread starter macrumors 6502a

    kwokaaron

    Joined:
    Sep 20, 2013
    #11
    That's interesting, didn't know that. Thought it was the firmware that was messing it around. However, some users have mentioned that their macs seem to be 'stuck' on the black screen even after downgrading.

    References:
    http://forums.macrumors.com/showthread.php?t=1818849
    http://forums.macrumors.com/showthread.php?t=1745984&page=2 (second last post)
    http://apple.stackexchange.com/ques...tartup-manager-after-downgrading-to-mavericks
     
  12. xWhiplash macrumors 68000

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    Oct 21, 2009
    #12
    I remember when people downgraded from Vista, and even 7 JUST because of the looks. I cannot go back to Mavericks now, it looks so old.

    The new look is much better. And does that mean you will never upgrade? Because the new look is probably here to stay for YEARS.
     
  13. thejadedmonkey macrumors 604

    thejadedmonkey

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    May 28, 2005
    Location:
    Pennsylvania
    #13
    I do (maybe) mean just that. Yosemite just doesn't cooperate with my eyes, and given the amount of system and app instability from Apple lately, I'm thinking an ultrabook with Windows 10 on it is probably the better choice. Of course, if I like the "all new redesigned 2015 macbook air", I'll probably get and install Windows 10 on that, if Windows runs alright on it.

    It all depends on what happens this May(ish).
     
  14. fotomarc macrumors regular

    fotomarc

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    May 8, 2014
    Location:
    Melbourne, Australia
    #14
    Small warning for those wanting to 'try' Yosemite

    You could move to other side of the planet!

    I don't just look at it l, I use it daily! Works fine for me!
     
  15. Traverse macrumors 604

    Traverse

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    #15
    Yeah, I mentioned that in my thread.

    Kind of annoying, but I'll live with it. I just wonder if it could cause issues for users running Mavericks.

    ----------

    That was not the case with me. I have FV enabled if that changes anything.
     
  16. grahamperrin macrumors 601

    grahamperrin

    Joined:
    Jun 8, 2007
    #16
    FileVault 2, Recovery OS, the recovery slice and versions of Mac OS X

    Earlier:

    I wasn't sure exactly what was meant by that.

    Consider that with FileVault 2, the early boot process for OS X uses the recovery slice (partition) to present users with the option to unlock the OS X slice.

    Here for example:

    Code:
    sh-3.2$ diskutil list disk0 | grep Apple_Boot
       3:                 Apple_Boot Boot OS X               134.2 MB   disk0s3
       5:                 Apple_Boot Recovery HD             650.0 MB   disk0s5
    sh-3.2$ diskutil mount readOnly /dev/disk0s5
    Volume Recovery HD on /dev/disk0s5 mounted
    sh-3.2$ defaults read /Volumes/Recovery\ HD/com.apple.recovery.boot/SystemVersion
    {
        ProductBuildVersion = 13F34;
        ProductCopyright = "1983-2014 Apple Inc.";
        ProductName = "Mac OS X";
        ProductUserVisibleVersion = "10.9.5";
        ProductVersion = "10.9.5";
    }
    sh-3.2$ diskutil unmount /dev/disk0s5
    Volume Recovery HD on disk0s5 unmounted
    sh-3.2$ 
    In my case that's slice 5 of disk 0 (zero). Your Recovery OS may have a different slice number.

    Essentially: check whether your Recovery OS is at Mac OS X 10.9.5. If not, it'll be timely to use Apple's full installer for that version of OS X.

    Kernel Programming Guide: The Early Boot Process
     
  17. Traverse macrumors 604

    Traverse

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    Mar 11, 2013
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    Here
    #17
    I had a fully bootable (and recovery drive creating) OS X 10.9.5 USB Drive I created with terminal. I did not use internet recovery.
     
  18. jbarley macrumors 68040

    jbarley

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    Jul 1, 2006
    Location:
    Vancouver Island
    #18
    actually they'd have to move to the other 'Hemisphere', depending on where they are now that could be either north or south.
     
  19. smirking macrumors 65816

    smirking

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    Aug 31, 2003
    Location:
    Silicon Valley
    #19
    It's buggy for some of us. Not "end of the world Windows 8 suddenly looks awesome" sort of buggy, but still annoying.
     
  20. snsking macrumors 6502

    snsking

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    Jun 10, 2013

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