While they offer fast speeds, solid-state drives (SSDs) are still pricey, and your costs can suddenly increase if you want to boost the storage when buying a Mac mini or an iMac. However, both Macs support high-performance USB 3 and Thunderbolt 3, and you can use this help offset the costs of getting more storage.

If the prices for high-capacity SSD upgrades for the Mac mini and iMac make you balk, you can get a more affordable external USB 3 or Thunderbolt 3 hard drive. Then, to get the most out of the speed of the SSD in the Mac mini or iMac, you can split your system and apps to one drive, and your user files to another.

With a Mac mini, the two standard configurations come with a 128GB or 256GB SSD, which you use to storage macOS. Then you attach a high-capacity external drive (SSD, hybrid, or even a fast hard drive) for your user files, which would include music and photos.

[ Further reading: Best NAS boxes for media streaming and backup ]

With an iMac, you’ve got options depending on which model you choose. On the two lower-end iMacs, opt for a 1TB Fusion drive (a $100 upgrade), and hold user files there, while using an external lower-capacity external SSD for your system. On the highest-tier iMac, pick a 256GB SDD (also just $100 more than the 1TB Fusion drive) for the system and use an external high-capacity drive for user files.

Check around for options for external drives, as prices can vary by large factors. For an hard drive, try to get a 7200-rpm drive. USB 3.0 or 3.1 will be fast enough for user files with an hard drive or hybrid drive, as well as for an SSD for the system drive.

How you start this split depends on where you’re starting from:

  • If you’re upgrading to a new Mac, and you can’t migrate your entire existing Mac to the system volume’s capacity as described above:
  1. Set up a new account on your new Mac as a placeholder, which will also act as a backup administrator account in case anything goes wrong with the other drive.
  2. Use Migration Assistant to move everything from your old Mac, Time Machine backup, or clone to your new Mac except your user files.
  3. When complete, create a new account with the same name and details as the user account or accounts you want to host on the other, higher-capacity drive.
  4. Copy your user directories to the other drive.
  5. Follow the instructions below to point your user’s directory location to the other drive.
  • If you have an existing Mac and want to shift user files to a higher-capacity drive:
  1. Create a new administrator account on the drive that has your system on it. This will serve as an emergency account in case something goes wrong with the other drive.
  2. Move your user directories to the other drive at the root level, rather than nested inside a Users folder. (You can do a simple drag and drop.)
  3. Follow the instructions below to point your user’s directory location to the other drive.

Repointing user directories is easier than it seems. Apple doesn’t advise it, but it does support it.

  1. Make sure you’re booted into the startup volume you intend to use to hold your system.
  2. You need to be logged into any account other than the one (or ones) for which you’re re-pointing the home directory location.
  3. Open the Users & Groups preference pane.
  4. Click the lock icon and enter your administrative password.
  5. Right-click the user for which you want to point to files on the other drive and choose Advanced.
  6. Click the Choose button next to the Home Directory field.
  7. Select the director on the other drive and click Open.
  8. Click OK.
mac911 choose other home directory
An Advanced Options dialog box lets you switch the user directory. Be careful you don’t accidentally make any other changes.

Now log into the user account you just created and make sure everything works as expected. Launch iTunes, launch Photos, launch Mail, and check iCloud and other settings.

For a less-technical solution, you can use settings in iTunes and Photos to point just those libraries to a separate drive, but I find it’s easier to have your entire user directory in one place.

This Mac 911 article is in response to a question submitted by Macworld reader Dave.

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