Sat Sep 17, 2022 4:09 am
It sounds like the MultiDock 10G is only connected to the computer using USB 2.0 speeds (480 Mbps) rather than USB 3.1 Gen 2 speeds (10 Gbps). Although USB 2.0 has a maximum interface bandwidth of 480 Mbps (60 MB/s), due to interface overhead (and a few other factors), have real world transfer speeds in the range of 35 to 40 MB/s, which seems to be inline with what you are seeing.
Usually the causes of this are some kind of cable or port issue. For example, a lot of USB-C cables designed for charging purposes only support USB 2.0 data speeds as they lack the additional data wires internally to support USB 3 data transfers.
I've also seen situations where USB 3 capable ports don't always negotiate USB 3 speeds (even when using a USB 3 compatible cable). Sometimes this is due to connection related issues and disconnecting and reconnecting the cable improves things.
Even with USB 3.1 Gen 2 speeds, things are never going to be as fast through the MultiDock 10G as with the internal SSD. USB 3.1 Gen 2 bus speeds are 10 Gbps (1250 MB/s) at the interface level, but due to overhead and other issues, real world maximum performance you can expect at the port level is around 900 MB/s or so. But since the MultiDock 10G uses SATA 3 (6 Gbps) based connections to the actual drives themselves, the maximum throughput possible to a single drive is even lower, usually around 500 MB/s maximum after accounting for SATA interface overhead (and could be less depending on the drive).