Install Mojave on another drive

MoerBoer

macrumors regular
Original poster
Jan 27, 2018
120
59
I finally sourced a RX 570 and I can now upgrade to Mojave.

I would prefer doing a clean install on another drive on my cMP 5.1, and keeping my existing High Sierra drive as is.
Is this possible now that I don't have my stock HD 5870 in anymore?
 

DeltaMac

macrumors G3
Jul 30, 2003
9,591
2,351
Delaware
Of course.
Boot to Mojave installer.
Run "Reinstall macOS", choosing your other drive as the destination. Could be internal on a different slot in your cMP, or external. This will be best, I think, on a blank partition, or an erased drive, whatever you have. That gives you an absolutely clean install. Then, if you like, when it begins a new-user setup on that drive, you will have the choice of migrating from another drive. You can then migrate from your High Sierra drive, leaving your High Sierra drive untouched, and your new system with everything from the High Sierra system drive, upgraded to use with Mojave. Or, just ignore the migration screen, if you want a simple/clean install of Mojave.
BTW, the Mojave install will automatically change your blank partition to APFS. There's no need to reformat that yourself, the Mojave installer will take care of that for you. It will not change the format of other partitions on that same drive (if you have other partitions on that other drive :cool: )
 
  • Like
Reactions: MoerBoer

MoerBoer

macrumors regular
Original poster
Jan 27, 2018
120
59
Thanks so much for the detailed response DeltaMac!

Much appreciated.
 

FazzMac

macrumors newbie
Feb 26, 2019
25
5
Of course.
Boot to Mojave installer.
Run "Reinstall macOS", choosing your other drive as the destination. Could be internal on a different slot in your cMP, or external. This will be best, I think, on a blank partition, or an erased drive, whatever you have. That gives you an absolutely clean install. Then, if you like, when it begins a new-user setup on that drive, you will have the choice of migrating from another drive. You can then migrate from your High Sierra drive, leaving your High Sierra drive untouched, and your new system with everything from the High Sierra system drive, upgraded to use with Mojave. Or, just ignore the migration screen, if you want a simple/clean install of Mojave.
BTW, the Mojave install will automatically change your blank partition to APFS. There's no need to reformat that yourself, the Mojave installer will take care of that for you. It will not change the format of other partitions on that same drive (if you have other partitions on that other drive :cool: )
Where can I find my Mojave Installer? I have a 2018 machine that came with Mojave already installed, where is the installer tucked away at for me to install on an external hard drive?

Thanks!