Overall summary of a year’s testing external hard disks and SSDs ranging in cost from $50 to more than $200 per TB. Which is best?
hard disk
Two reasons for paying more and using SSDs are that they’re faster and more reliable. Data on failure and reliability don’t appear as clear as the ads, though.
With the right enclosure, a Samsung 980 PRO NVMe SSD delivers transfer speeds of around 2.8 GB/s. Does that make booting from it any faster, compared with an SSD at half the speed?
It depends whether you’re going to boot macOS from it, on the space required for snapshots, and how large they could become. And there’s more.
File data stored towards the periphery of the disk is read and written nearly twice as fast as that near the centre. How to take advantage of this.
Which is faster with a hard disk: using APFS or sticking with HFS+? Are there any differences in their performance on SSDs?
Which of the external disks tested can be used to boot from? Do they work reliably with Secure Boot? Could you boot from an external hard disk?
Internal or external? Hard disk or SSD? USB or Thunderbolt? Cooled or compact? Branded or separates? An external boot disk? Do you have a return and refund option?
M1 Macs don’t support SMART monitoring over USB-C, forcing us to choose between Full Security without SMART, or Reduced Security with SMART support.
Not long ago, many of us paid for software which tied our Macs up for hours every month or so, defragmenting their hard disks. Why, and why not now?
The Eclectic Light Company 