Can you downgrade a new 2017 iMac to High Sierra?

Discussion in 'iMac' started by EightyTwenty, Jul 28, 2019.

  1. EightyTwenty macrumors 6502a

    Joined:
    Mar 11, 2015
    #1
    If I purchased a new one that comes with Mjave installed, can I download a copy of High Sierra and install that instead?

    It look like the 2017 iMac originally shipped with Sierra.

    Thanks.
     
  2. DeltaMac macrumors G3

    DeltaMac

    Joined:
    Jul 30, 2003
    Location:
    Delaware
    #2
    Should work.
    The simplest test would be to boot to a High Sierra bootable installer. If you can boot to that, you should be able to continue with the install. (Erase the internal drive first, using Disk Utility, then reinstall macOS (High Sierra, if that's what you want)
     
  3. EugW macrumors 603

    EugW

    Joined:
    Jun 18, 2017
  4. EightyTwenty thread starter macrumors 6502a

    Joined:
    Mar 11, 2015
    #4
    I’ve read that starting with Mojave, Apple got rid of subpixel anti-aliasing making text blurry on non-retina screens.

    I’m debating between the 2017 2K for $1179 or the 2019 4K for $1445.
     
  5. EugW macrumors 603

    EugW

    Joined:
    Jun 18, 2017
    #5
    I would definitely not recommend a non-Retina model. You don’t need subpixel anti-aliasing on Retina screens.

    However, in Mojave there is a terminal command to reactivate subpixel anti-aliasing if you want.

    It should be noted that Apple is supporting 4K video streaming only on the 2019 models.
     
  6. chrfr macrumors 604

    Joined:
    Jul 11, 2009
    #6
    Whichever you choose, don't get one that has a 5400 rpm disk in it; you'll find it very slow.
     
  7. EightyTwenty thread starter macrumors 6502a

    Joined:
    Mar 11, 2015
    #7
    I plan on booting from a SSD via USB 3.1 or thunderbolt. Samsung T5 or X5.
     
  8. Fishrrman macrumors P6

    Fishrrman

    Joined:
    Feb 20, 2009
    #8
    If you get a 21", MAKE SURE that you get one with enough RAM -- because adding more later requires disassembling the iMac.

    If you plan on "booting externally", do it right the first time by getting a Samsung X5 instead of a t5.
    Connected via thunderbolt3, the X5 will give you 4-5x the speed of the t5.

    I'd really recommend that you get an Apple-refurbished 2017 27" 5k iMac with a fusion drive (at least).
    In that case you can get 8gb of RAM and add more yourself later... IF you find that you need it.

    The fusion drive (at least the 2tb version) will be pretty "snappy" right out-of-the-box.
    This way, you get a very usable Mac from the get-go, and can add the X5 later.
     
  9. EightyTwenty thread starter macrumors 6502a

    Joined:
    Mar 11, 2015
    #9
    This is good advice. It’s just that the 5K iMac is so much more expensive, especially in Canada. I also find the 27” screen overwhelming (never used anything above 19.5”). RAM upgrade ability is a major advantage. I wish they allowed for that with the 4K iMac as well.
     
  10. Fishrrman macrumors P6

    Fishrrman

    Joined:
    Feb 20, 2009
    #10
    I'll reckon that a 27" refurbished iMac with a 2tb fusion drive won't cost you all that much more than would a 21" refurbished iMac with 16gb of RAM, along with a Samsung X5 drive (either 512gb or 1tb).
     
  11. alisalem macrumors member

    Joined:
    Apr 12, 2013
    Location:
    Mississauga, ON
    #11
    You can enable it with this command: defaults write -g CGFontRenderingFontSmoothingDisabled -bool FALSE
     
  12. EightyTwenty thread starter macrumors 6502a

    Joined:
    Mar 11, 2015
    #12
    I’ve read that is not a true fix as there were other changes made to font rendering from High Sierra to Mojave.

    Do you have a 2K iMac? Have you used that code yourself?
     
  13. alisalem macrumors member

    Joined:
    Apr 12, 2013
    Location:
    Mississauga, ON
    #13
    I tried it on my Dell 27" 2K monitor at work and font rendering looked identical to High Sierra. This is coming from a web designer btw.
     
  14. alien3dx macrumors 6502a

    alien3dx

    Joined:
    Feb 12, 2017
    #14
    no blurry. get ssd i'm using externl ssd to counter the slowness
     
  15. Infinite Vortex macrumors regular

    Infinite Vortex

    Joined:
    Mar 6, 2015
    #15
    I find that the price of the iMac 5K isn't much different to that of the 4K especially when you're upgrading RAM. In the 5K you can take the base and upgrade at any time via 3rd party… the 4K you need to do it there and then and at Apple's inflated pricing. My 32GB RAM was cheaper than the 16GB that Apple would have sold me in the 4K.

    Also, when comparing the storage, I'm not sure with the 2017 but if you look at the 2019 the 5K comes with a 1TB Fusion where the 4K comes with 1TB HDD. While not the same as going all SSD the Fusion will significantly outperform HDD alone. I find that going SSD, no matter which model you want, is the way to go even though it costs a bit more given NVMe will kill anything else you can do.

    I do get your budget is probably different to mine but if you're on a tight budget you need to consider what your cost per year will be. For instance, my iMac is a late-2015 and I should replacing it this year or next. Given the state of flux that macOS is in (with maybe Marzipan coming real soon) and I'm still in High Sierra, I'm not feeling any need to change it. So if I keep it an extra year that's 33% more use at significantly less than 33% more expenditure. Comparing the 2019 again, the quad-core i3 in the bottom 4K is significantly lesser than the 6-core i5 in the bottom 5K which can affect your ability to keep it for the same number of years.

    And you get used to the 27" pretty fast. I was hesitant myself given its at a width now that the need to turn my head to see both edges is coming in… but no way I'd buy anything less going forward.
     

Share This Page

14 July 28, 2019