I can't seem to locate a YouTube video that claimed their external SSD drive(s) were faster running through an OWC dock vs. directly connected to the M1 MacMini. How can this be? Wouldn't you think a direct connection to the M1 would be faster?
I've been eyeing up external SSD drives for my M1 MacMini and the market totally confuses me on price vs. performance.
There are many 30+ page threads in the Apple Silicon section of the forum about this. The summarized version is that Apple released M1 Macs with an absolutely abysmal I/O implementation, which becomes the most obvious at the 2 most popular port use cases - connecting external displays and external drives. Basically, many drives you connect to your M1 Mac will perform significantly worse (often >50% slower) in comparison to older Intel Macs or PCs. This is especially bad with 10Gbps USB drives like the super popular Samsung T5. People discovered that they can alleviate this issue somewhat by unintuitively plugging external USB drives into their thunderbolt docks because the docks contain a separate off-the-shelf USB3 controller to drive their USB ports, which works as expected.
You might think that Apple simply missed out on implementing the USB aspect of the thunderbolt protocol properly (even though thunderbolt is, by definition, a superset of USB3.1 spec with 40Gbps bandwidth and DisplayPort streams and must support all USB devices), since all Apple engineers only use TB3 drives or something, but you'd be wrong. Many TB3 drives exhibit similar speed issues, with some even causing instant kernel panics and shutdowns (while working completely fine everywhere else, including Intel Macs). Head-scratchingly, many NVMe drives that seem to not work well with M1 are some of the most popular ones on the market, so it's an issue that really should've been caught during development. Nonetheless, I'd say that there are somewhat less reports of issues with TB3 versus USB drives, but this might simply be based on less people having them.
I just spent last 2 weeks trying to figure out which external drive to buy, reading through basically all material available on the internet regarding people's experiences focusing on speed and compatibility with AS Macs. The most compatible and performant option seems to be a self built drive using a WD SN750 SSD in an Acasis USB4.0 NVMe enclusure, which reaches about 2500MB/s write and 2700MB/s read speeds. However, you will only save about $50-$100 when compared to the 2TB version of the OWC drive, so I'd say that the price isn't completely insane in the current market. A cheaper, but slower option would be going with WD SN550 DRAM-less SSD and the same Acasis enclosure, which has also been reported to work fine.
One thing I would definitely note that the
review above is done using an Intel Mac so this might not be an accurate representation of its performance on M1 (although it would be extremely embarrassing for OWC to release a drive that doesn't work perfectly with M1 at this point).