Bring new life to an old Intel-based iMac or Mac mini [Setups]


Commenters offered good advice on speeding up this Intel-based iMac setup.
Commenters offered good advice on speeding up this Intel-based iMac setup.

If you have an aging Intel-based iMac or Mac mini that’s slowing down like an old codger, today’s featured iMac setup shows a relatively simple way to revitalize your machine and keep using it.

All you need is an external solid state drive (SSD) and the knowledge, below, to make it your computer’s replacement startup disk.

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External SSD can revitalize an Intel-based iMac or Mac mini

Redditor vmcommo (“Com”) showcased their simple iMac setup in a post entitled, “slow as all hell, but i still love it to death.”

Com runs an Intel-i5 iMac from 2012 and uses a Keychron Q2 customized mechanical keyboard with Gateron Oil King switches and a Logitech wired gaming mouse.

And that’s pretty much the whole setup, other than an expensive Herman Miller Embody chair and some primo audio gear, like Audeze and Grady over-ear headphones, a Schiit Magni headphone amplifier and a iFi Zen digital-to-analog converter (DAC).

“I like that you prioritize audio quality and your chair before buying the latest Mac equipment,” noted a commenter. “Audio and chairs are respectable quality of life improvements.”

And apparently “slow as hell” in the post’s title is all it took to attract some helpful advice from commenters.

“I still have a couple of 21.5 and 27[-inch] iMacs around the house,” one said. “All with an SSD and updated to macOS Ventura using OCLP [OpenCore Legacy Patcher]. Love the design and they still all work pretty well.”

OCLP is a Python-based software that lets older Macs install and run macOS Ventura, Apple’s latest (currently 13.5.2).

Stick an external SSD on there with Velcro

“Get an external SSD and 3M Velcro it to the back of the stand,” another person added, describing what do in a bit more detail. “Clone your HDD onto it and use it as starting drive.”

“Seems like a good idea!” Com replied. “I’ll try it out! Thanks!”

“It will go from a useless computer to very capable,” the second commenter assured Com.

So why do it?

As the second commenter said, a modern external SSD as a startup disk can boost an old Intel-based iMac or Mac mini’s performance.

Apple’s discussion forums are perfectly up-front about the benefits of using an external SSD as a replacement startup disk.

As Apple says:

Your USB 3-equipped Mac with a hard disk or Fusion Drive can have improved system performance by connecting to an external solid-state drive (also known as an SSD). An external SSD as a startup disk can give your Mac additional performance for system responsiveness, apps, startup, and more.

Using an external SSD as a startup disk is supported by any Mac with an Intel processor with an Apple hard disk or Fusion Drive, with USB 3 ports, running macOS High Sierra 10.13 or later.

What you need

You need an Intel-based Mac mini or iMac, of course (see below for specific models).

For Mac mini or for iMacs from late 2015 or earlier, you probably need a USB-C to USB-A adapter cable to connect to an SSD.

As for your choice of SSDs, Apple recommends one it sells — LaCie Mobile SSD Secure USB-C Drive. If you choose another, just make sure it’s big enough to fit all your content, runs USB 3.2 and supports startup-disk functionality for Mac.

And if you want to attach the drive to your iMac’s stand, like the person above suggested, you need Velcro or another way to fasten it.

Steps to follow

For more detail on each of these steps, see Apple’s instructions.

  1. Connect and erase the external SSD.
  2. Install macOS to the external SSD (OS can be as new as Ventura or as old as Catalina, depending on the age of your computer and whether or not you use special workaround software like OCLP, above).
  3. Use Migration Assistant to move your content to the external SSD.
  4. Assign the external SSD your default startup disk in the Startup disk section of System Settings.

Which Macs can benefit?


  • iMac (Retina 5K, 27-inch, 2019)
  • iMac (Retina 4K, 21.5-inch, 2019)
  • iMac (Retina 5K, 27-inch, 2017)
  • iMac (Retina 4K, 21.5-inch, 2017)
  • iMac (21.5-inch, 2017)
  • iMac (Retina 5K, 27-inch, Late 2015)
  • iMac (Retina 4K, 21.5-inch, Late 2015)
  • iMac (21.5-inch, Late 2015)
  • iMac (Retina 5k, 27-inch, Mid 2015)
  • iMac (Retina 5K, 27-inch, Late 2014)
  • iMac (21.5-inch, Mid 2014)
  • iMac (27-inch, Late 2013)
  • iMac (21.5-inch, Late 2013)
  • iMac (27-inch, Late 2012)
  • iMac (21.5-inch, Late 2012)

Mac mini

  • Mac mini (Late 2014)
  • Mac mini (Late 2012)

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If you would like to see your setup featured on Cult of Mac, send some high-res pictures to Please provide a detailed list of your equipment. Tell us what you like or dislike about your setup, and fill us in on any special touches, challenges and plans for new additions.

LaCie 2TB Mobile SSD Secure USB-C Drive

This large external solid state drive could serve as your old iMac or Mac mini's new startup disk.

Buy Now
03/07/2024 12:41 am GMT


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