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I want to connect 3 USB 3.0 devices to my MacBook Pro 2016. I'd like to do it through a single USB-C port using this a USB-C to 3 USB 3.0 hub like this one. Question!

When I connect a single 3.0 device through the hub the maximum theoretical speed is 5Gb/s, right? If I connect two 3.0 devices and read from them at the same time. Will each of them still transfer data with the speed of up to 5Gb/s or is it going to slow down? In other words, when the device says it provides 4 3.0 ports, does it use 3.0 protocol to talk to the laptop, and thus has to 'share' the 5Gb/s bandwidth among all the devices? OR does it take advantage of the usb-c port. In the case of the latter, does it then have 10 Gb/s to distribute (usb 3.1 protocol) or 40(thunderbolt 3).

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You won't get faster than USB 3.0 speed on the link to the Mac or any of the hub links. (You'd need a thunderbolt 3 hub for that.)

  • USB 3.0 theoretical speed is 5 Gbit/s
  • USB 3.1 theoretical speed is 10 Gbit/s

Theoretically - when you have a hub, there is overhead and losses and those depend on the quality of the chipset in the hub.

In practice - what is going to be providing or consuming data at even 3 Gb/s - not much. Get the hub you like for the support and price and warranty and when you have an actual performance issue - you can profile it and get a second hub or offload the one device to another port.

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  • Thanks for the answer. So in principle is it possible to have a hub which would talk to the laptop at 40 Gb/s but talk to devices at 5?
    – ivanibash
    Commented Dec 4, 2016 at 20:32
  • no - in principal - 3.0 tops at 5
    – bmike ♦
    Commented Dec 4, 2016 at 20:35
  • I understand that 3.0 tops at 5. But the laptop's port supports usb 3.1/thunderbolt 3. So the question is, can it talk to the laptop with one protocol but talk to devices with another.
    – ivanibash
    Commented Dec 4, 2016 at 20:42
  • Yes, that is entirely possible. As an extreme example, you can buy a chassis that connects to Thunderbolt and lets you insert any PCIe card for which you have drivers. That could be a USB3 interface card :-) Ofcourse to make something useful in practice it would look like a small USB-hub with just the USB3 and TB3 ICs built-in.
    – jksoegaard
    Commented Dec 4, 2016 at 20:50
  • Cool, I feel that this answer answered the original question about USB hub though so I'm marking as accepted.
    – ivanibash
    Commented Dec 5, 2016 at 12:54

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