Otherwise, you can use Time Machine to backup your old SSD to external storage, then restore after installing the new SSD.

You can enter recovery mode - (reboot then hold down 'Command key + R') and use disk utility to 'restore' from your old SSD to the new one, or use the Super Duper app to perform the clone, then switch the drives.

If you are running a version of MacOS before High Sierra (10.12.6 or earlier), and don't plan to upgrade, then stick with the Jetdrive 820 and 825 products.

*Note, the Transcend Jetdrive 850 and 855 products are NVMe based, therefore require MacOS High Sierra or above to be running before you attempt to install the SSD.

The Transcend Jetdrive 825/855 SSD upgrade kits allow you to clone your existing OS/app setup by first installing the new SSD in an external enclosure and attach to your system via the USB port.

If you are buying the 'Blade-only' products then you'll also need the Essential Electronics Toolkit and Torx T6 Screwdriver.

To upgrade or replace the 'Blade' SSD, see the product options from OWC and Transcend on the left.

If you have a ‘Fusion drive’ setup, then you’ll need to split the fusion drive first and then perform the clone operation.

You can keep your old 2.5-inch HDD in the enclosure for external storage.

To clone your existing OS/app setup first, purchase a Cloning/Data Transfer Cable or 2.5-inch HDD/SDD enclosure to connect your new SSD to your mac, then use the Super Duper app to perform the clone, then switch the drives.You’ll need a larger 2.5-inch HDD or 2.5-inch SSD, the Logic Board Removal Tool, and the Essential Electronics Toolkit. To upgrade the existing 2.5-inch drive(s) to a larger capacity HDD or to a high performance SSD, follow this guide.However, the cable to connect this SSD to the PCIe connector is not present unless the system is configured with a 'Fusion Drive' at the time of initial purchase.

The current 'Late 2014' models have a Serial ATA (6 Gb/s) connector for a 2.5-Inch hard drive or SSD in addition to a proprietary PCIe connector for a 'blade' SSD.If your Mac Mini is the SSD-only version, then it will not have the necessary SATA connector to add in a 2.5-inch SATA hard drive or 2.5-inch SATA SSD.

By default, this model is configured with a 1 TB 'Fusion Drive' (which combines a 1 TB 2.5-inch hard drive attached via a 6Gb/s SATA port and a 128GB ‘Blade’ SSD), but could also be configured at the time of purchase with a 256 GB ‘Blade’ SSD (instead of the 1 TB 'Fusion Drive”).Sadly, the RAM in this MacMini cannot be upgraded, but you can upgrade the internal hard drive for extra space or upgrade to an SSD for much better performance.

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