External Graphics card on a dual USB 3.0 Laptop

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I have a question about adding a external graphics card to my laptop. It runs most games great on low settings but I would like to bump it up a bit. I have heard that USB-3.1 has display port and 10gb/s capabilities.

I know USB 3.0 is 5gb/s and I was wondering if I could somehow couple two of my USB 3.0 slots together and convert them to a USB type C connector.

It would give me 10Gb/s but I don't know what would be required to get them to work together and have display port capabilities. If I could get it converted I could buy one of the USB-C graphics card docks and use an external monitor and graphics card. Is this possible or will it ever be? Thanks you. (I know that I could use m-PCIe but my laptop is not designed to be taken apart and it would be too bulky for my situation. My laptop does not have an Express card slot so that would not work either.) I currently have Intel HD Graphics 4600.

Best Answer

I think that you are close, but not quite. We have:

  • USB 2.0 (speed to low with a theoretical max of 480Mbit/sec)
  • USB 3.0 (Speed up to 5Gbit/sec) "Superspeed". Usually with blue coloured connectors.
  • USB 3.1 (speed up to 10Gbit/sec). Usually with red coloured connectors.
  • USB 3.1 (speed up to 10Gbit/sec) with the new type C plug. No display capabilities are derived from the USB interface.

Also we have:

  • Displayport which is a graphics output intended to replace the older DVI and HDMI connnectors.
  • Thunderbolt-1, which started as light peak, a fast link over optical cables. However this turned out not to be an economical option and eventually transformed into a 10Gbit/sec link over copper named Thunderbolt. Display port used packets of data which allowed the data stream to be used for both PCI-e data and graphics data. (PCI-e lanes over a cable. Optionally multiplex PCI-e and DP port information)
  • Thunderbolt-2 allowed two Thunderbolt-1 channels to to combined, effectively doubling the speed compared to Thunderbolt 1.
  • Thunderbolt-3 is faster yet (40Gbit/sec) and used a new connector, same as USB-C. Tunderbolt 3 can transport display port information. It can also fall back to the USB 3.1 protocol. If used in USB mode it does not transport PCI-e or DP information.


So, to summarise above:

I know USB 3.0 is 5Gb/s and I was wondering if I could somehow couple two of my USB 3.0 slots together and convert them to a USB type C connector.

  1. You cannot simply combine two USB 3.0 ports and magically get a 10Gbit/sec port. In theory you could build a deivce with a 10Gbit/s port and drivers to feed it with data from two 5.0Gbit/sec ports, but I know of no such device.
  2. Just having 10Gbit/sec output does not magically add display capability.

That leaves you with a few choices:

  1. For gaming, buy a cheap desktop. Those are still much better for gaming.
  2. Or open the laptop and find a mini PCI-e graphics card (Check if it can get enough cooling and enough power!).
  3. Or open the laptop and extern PCI-e outside and use an external graphics card. (similar to how you can to that with a exprescard slot). I understans that this is not something done lightly and it would turn your laptop into a fixed location (or at least very difficult to move) desktop.
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