Looks like no one’s replied in a while. To start the conversation again, simply ask a new question.

Running OS on external SSD, then transferring to a new Mac!

So i have a 2014 Mac mini, and to speed things up I somewhat recently decided to run the entire OS off an external Samsung SSD. It’s worked great since, but looking to upgrade to the new m1 Mac mini.


My question is basically, how would I go about this? Of course the new Mac will have Big Sur installed, the SSD has Mohave I believe. I just don’t know how easy it’ll be to run things off that external SSD.


Does the SSD have to be reformatted to run on the new OS?


Any tips would be helpful!

Mac mini, macOS 10.14

Posted on Sep 2, 2021 6:04 PM

Reply
Question marked as Best reply

Posted on Sep 3, 2021 5:14 AM

Truability wrote:

So i have a 2014 Mac mini, and to speed things up I somewhat recently decided to run the entire OS off an external Samsung SSD. It’s worked great since, but looking to upgrade to the new m1 Mac mini.

My question is basically, how would I go about this? Of course the new Mac will have Big Sur installed, the SSD has Mohave I believe. I just don’t know how easy it’ll be to run things off that external SSD.

Does the SSD have to be reformatted to run on the new OS?

Any tips would be helpful!

First off, the new M1 Macs can only run Big Sur period. Not just because it is a new CPU architecture, but has been true with Macs for a very long time that they cannot run an OS earlier than the one they were released with.


Second, with any external SSD other than a Thunderbolt 3/4 SSD will run significantly slower than when using the internal SSD, Generally speed tests on the internal SSDs on M1 Macs are in the neighborhood of 2800-3000 megabytes per second which currently only Thunderbolt, nVME based drives can come close to.


Also, big note since you are running Mojave, Big Sur will only support 64 bit apps so any 32 bit apps you are currently using in Mojave will be useless and either updates, upgrades, or alternatives will need to be found. While you can use Migration Assistant to transfer things from the current external drive, you need to be aware of the issue with apps.

5 replies
Question marked as Best reply

Sep 3, 2021 5:14 AM in response to Truability

Truability wrote:

So i have a 2014 Mac mini, and to speed things up I somewhat recently decided to run the entire OS off an external Samsung SSD. It’s worked great since, but looking to upgrade to the new m1 Mac mini.

My question is basically, how would I go about this? Of course the new Mac will have Big Sur installed, the SSD has Mohave I believe. I just don’t know how easy it’ll be to run things off that external SSD.

Does the SSD have to be reformatted to run on the new OS?

Any tips would be helpful!

First off, the new M1 Macs can only run Big Sur period. Not just because it is a new CPU architecture, but has been true with Macs for a very long time that they cannot run an OS earlier than the one they were released with.


Second, with any external SSD other than a Thunderbolt 3/4 SSD will run significantly slower than when using the internal SSD, Generally speed tests on the internal SSDs on M1 Macs are in the neighborhood of 2800-3000 megabytes per second which currently only Thunderbolt, nVME based drives can come close to.


Also, big note since you are running Mojave, Big Sur will only support 64 bit apps so any 32 bit apps you are currently using in Mojave will be useless and either updates, upgrades, or alternatives will need to be found. While you can use Migration Assistant to transfer things from the current external drive, you need to be aware of the issue with apps.

Sep 3, 2021 6:59 AM in response to woodmeister50

Good points! The SSD I have is a Samsung t7 so it is nVME based up to 1000/mb, blows my old Mac out the water, but yah pretty weak in comparison to the internal on the M1. My issue was not wanting to spend too much on the internal hard drive, and save by still using this Samsung ssd.


im in a bit of a storage war as always, but just realized I pay for 2TB of iCloud and only use 350gb atm. So I think what I’ll do is maybe buy the 512gb m1, take everything I really need from the Samsung drive and put it on iCloud, then format the Samsung and just use it as external storage (not run the OS off of it anymore).


I think then I can make it all work and stay and budget. Thank you to everyone for the help!

Running OS on external SSD, then transferring to a new Mac!

Welcome to Apple Support Community
A forum where Apple customers help each other with their products. Get started with your Apple ID.