File this as me just being curious.
I have an old computer (Dell gx280) that has a external usb 2.0 hard drive connected to it. I was trying to copy the files over a gigabit network connection to another computer and it was only transferring at approx. 2.5 megabytes a second. This was only using a small fraction of the gigabit network card in both the source and destination computer. I saw the CPU was maxed out on the source PC b/c of an application. Once I quit that application the CPU usage went back to essentially nothing. The copy job then jumped up to 14 megabytes a second and was using 30-35% of the gigabit connection.
The NIC and the USB ports are on the motherboard. How did the CPU usage slow this whole process down and was it impacting the network card, the USB port or both?