Further to my thread on performance differences with NTFS external drives on the M1 MacMini and a MBP16, I've found that the two machines connect to the same USB 3.1 external SSD at different speeds.
Here is the System Report output from my MBP16:
Note the connection speed of the AS Media enclosure is shown as 10 Gb/s
Here is the same disk on my new Mac Mini:
It only connects at 5 Gb/s.
This might explain (at least part) of the disk speed differences in BlackMagic Disc Speed Test, although 5Gb/s should be sufficient to get almost the same speed because the SATA3 disk is close to its maximum throughput. If the disk is capable, even a 5Gbps connection should allow for 500MB/s assuming 8/10 encoding on the USB connection.
Here is the System Report output from my MBP16:
Note the connection speed of the AS Media enclosure is shown as 10 Gb/s
Here is the same disk on my new Mac Mini:
It only connects at 5 Gb/s.
This might explain (at least part) of the disk speed differences in BlackMagic Disc Speed Test, although 5Gb/s should be sufficient to get almost the same speed because the SATA3 disk is close to its maximum throughput. If the disk is capable, even a 5Gbps connection should allow for 500MB/s assuming 8/10 encoding on the USB connection.
