Charlie Gibbs wrote: > Is the connector blue? It's a convention to make USB 3.0 connectors > blue, while USB 2 connectors aren't. My machine has a mix. > > https://en.wikipedia.org/wiki/USB_3.0
I would also start with this. USB3 (not only 3.0 but 3.x) are blue. Then you can use dd to determine speed (knowing USB2 is about 480Mbps which is equivalent of approx 40MB/s - AFAIR 100Mbps~=12MB/s) In reality it looks like this dd if=/dev/sdc of=/dev/null bs=512 status=progress 851034624 bytes (851 MB, 812 MiB) copied, 24 s, 35.5 MB/s SATA in active RAID for example dd if=/dev/sda of=/dev/null bs=512 status=progress 1397104128 bytes (1.4 GB, 1.3 GiB) copied, 5 s, 279 MB/s USB3 on RPi4 dd if=/dev/sda of=/dev/null bs=512 status=progress 3767485440 bytes (3.8 GB, 3.5 GiB) copied, 48 s, 78.5 MB/s regards
