How could Nintendo implement a Switch Pro?

[Pemalite]

Pyro as Bill said:

Laptops and egpus must face the same issue too mustn't they? How do these guys run TITANs and 970s through 10Gbps or HD7970s through 4Gbps?

https://www.techinferno.com/index.php?/forums/topic/6740-2012-15-macbook-pro-titan_z10gbps-tb1-akitio-thunder2-osx1010-nesone/&do=findComment&comment=103967

https://www.techinferno.com/index.php?/forums/topic/6962-2012-15-macbook-pro-gtx97010gbps-tb1-akitio-thunder2-win10osx1010-w4vz/&do=findComment&comment=107769

https://www.techinferno.com/index.php?/forums/topic/6766-2012-15-mbp-gt650m-hd79704gbps-tbec2-pe4l-21b-win10-rhodesie/&tab=comments#comment-104465

That is the Akitio Thunder2.
It is not using a derivative of USB, it is using dual Thunderbolt 2 ports which piggy back off PCI-Express.

https://www.anandtech.com/show/7049/intel-thunderbolt-2-everything-you-need-to-know
https://www.amazon.com/Akitio-Thunder2-PCIe-Box-intended/dp/B00LTAUTHE

The device itself was actually never designed for graphics cards anyway... And there is a performance penalty and is pretty low-latency.

But it is certainly higher bandwidth and lower latency than the Switch's USB port.

Pyro as Bill said:
You techies love it. When Nintendo put a PCI-E connection in the upgraded TX2 Switch, wouldn't any egpu still be severely limited by CPU? Would the egpu need to be built around the Tegra or could Nvidia use magic and allow any gpu to work?

Well... The extra GPU would mostly be used to drive improved visuals, so the CPU shouldn't be anymore limiting than it is currently.
nVidia in theory could leverage it's "Optimus" technology and allow any GPU to work, it isn't hard to beat the Switch's GPU capabilities, even the Geforce 1030 is faster.