I know modern Macs all have USB3 support, but now there's USB 3.1, USB 3.2, NVMe and of course thunderbolt (presumably multiple versions) and I am lost.
What does the 2020 Intel iMac 27" support? What does that mean for data transfer speeds? When buying an external drive what do I need to look out for to make sure it will be compatible with the fastest option?
Fastest theoretical is 2750MB/s with Thunderbolt-3, but that is expensive overkill for typical use and requires either a high-quality NVMe or a RAID array of lesser SSDs.
Unless you are doing video editing or working with other very large data sets I'd suggest looking for a more affordable USB-C / USB 3.1 gen-2 in the 1000-1250 MB/s range.
+1
If you need the absolute fastest (Thunderbolt 3), a LaCie Rugged SSD Pro External Drive with Thunderbolt 3 - Apple would be excellent.
However, a standard 1,000 MB/s SSD is usually plenty fast, such as a LaCie Mobile SSD Secure USB-C Drive - Apple.
Jack
There are multiple articles on the web about super fast drives such as Samsung's X5 Thunderbolt 3. None of them live up to their hyped speeds in the real world ... outside the test lab. All get quite hot and throttle back speeds to some degree. A few of the tests I read had speeds that dropped to half or 2/3 of claimed rates.
Best for our purposes have been drives that run in the claimed 1,000 MBps range attached to USB 3.1 Gen 2 ports on our 2020 27" iMacs. When attached to a USB A port, speeds top out at around 480-500 MBps with occasional bursts to maybe 540 MBps.
I've had outstanding performance and longevity with Samsung's T7. YMMV.
What is the fastest external storage supported on Intel 2020 27" iMac?
