How to run iMac from external SSD?

How to run iMac from external SSD?


Utilizing an external SSD to run your iMac can boost performance and provide additional storage. Discover how to set up and run your iMac from an external SSD for enhanced speed and flexibility.

Unlock the Power of Your iMac: Supercharge Your Performance with an External SSD!

To run your iMac from an external SSD, follow these steps:

  1. Selecting the SSD:
    • Choose a compatible external SSD with sufficient storage capacity and high read/write speeds for optimal performance.
  2. Backup Your Data:
    • Back up all important data on your iMac using Time Machine or another backup method to prevent data loss during the setup process.
  3. Connect the SSD:
    • Connect the external SSD to your iMac using a Thunderbolt or USB-C port. Ensure the SSD is properly recognized and mounted on your iMac.
  4. Format the SSD:
    • Open Disk Utility (Applications > Utilities > Disk Utility).
    • Select the external SSD from the list on the left.
    • Click on the “Erase” tab, choose a compatible format like APFS or Mac OS Extended (Journaled), and click “Erase” to format the SSD.
  5. Install macOS on the SSD:
    • Open the Mac App Store and download the macOS installer.
    • Launch the installer and select the external SSD as the installation destination.
    • Follow the on-screen instructions to install macOS on the external SSD.
  6. Set External SSD as Startup Disk:
    • Go to System Preferences > Startup Disk.
    • Select the external SSD with the newly installed macOS as the startup disk.
  7. Restart and Boot from the External SSD:
    • Restart your iMac.
    • During startup, hold down the Option (⌥) key until the Startup Manager appears.
    • Select the external SSD with macOS as the startup disk and press Enter to boot from it.
  8. Verify the SSD Boot:
    • Once booted from the external SSD, check System Information (Apple menu > About This Mac > System Report > SATA/SATA Express) to confirm that your iMac is running from the external SSD.

Running your iMac from an external SSD can significantly enhance performance, providing faster read/write speeds and additional storage capacity. However, it’s essential to keep the external SSD connected whenever you want to use your iMac. Additionally, ensure your external SSD is compatible and offers sufficient performance to meet your needs before proceeding with the setup process.

How do I format an external SSD for macOS installation using Disk Utility?

When preparing an external SSD for macOS installation using Disk Utility, it’s essential to follow specific formatting requirements and procedures to ensure compatibility and successful setup. To begin, plug the external SSD drive into your iMac’s available port and launch Disk Utility, located in the Utilities folder within the Applications folder or accessible via Spotlight. Once open, select the external SSD from the list of external devices or external disks shown in Disk Utility’s sidebar.

Next, to prepare the external SSD for macOS installation, choose the “Erase” option from the Disk Utility menu bar or right-click on the external SSD and select “Erase.” Here, you’ll have the opportunity to specify the desired disk format. It’s recommended to select “APFS” (Apple File System) or “Mac OS Extended (Journaled)” as the disk format, depending on your macOS version and compatibility requirements. Assign a suitable name for the external startup drive, ensuring it’s recognizable and distinguishes it from your internal startup drive. Additionally, selecting “GUID Partition Map” as the scheme ensures the external SSD is properly formatted for use as a bootable drive. Once these formatting settings are chosen, proceed with erasing and formatting the external SSD, transforming it into a stable and bootable drive suitable for macOS installation and use as a startup device.

Does macOS check if booting from the external SSD was successful?

To verify successful booting from an external SSD on macOS, several system checks and indicators within the operating system can confirm the active startup drive. Navigate to the Apple menu in the top-left corner of the screen and select “About This Mac.” Within the window that appears, click on “System Report.” In the left-hand column of the System Information window, under “Hardware,” select “SATA/SATA Express.” Here, information regarding internal and external drives connected to your iMac is displayed. Check the listed details to identify the external SSD drive, which should indicate its connection status, such as “External” or its specific model name. This confirms that the external SSD is recognized as an external drive and is currently active within the system.

Another method to verify the boot drive is by accessing the “Startup Disk” section within System Preferences. Navigate to the Apple menu, choose “System Preferences,” and then select “Startup Disk.” Here, you’ll see a list of available startup devices, including the internal drive and the designated external startup drive (external SSD). The active startup disk, marked by a selected checkbox or a highlighted entry, confirms that the external SSD is currently set as the default startup disk for your iMac. These checks within the System Information and Startup Disk preferences provide clear indications that your iMac is indeed running from the external SSD as the selected and active bootable device, ensuring a stable and reliable computing environment sourced from the external startup drive.