It's my understanding (though I haven't tried it with a touch screen) that the one USB-C connection should be all you need. 

While I don't know much about it, The Verge did a pretty detailed write-up of a 17" USB-C option: https://www.theverge.com/21311820/ananta-usb-c-portable-touchscreen-display-review-price-specs-features ,

-Ben S.

Thanks, but that nifty looking monitor is a Kickstarter campaign maybe shipping in September, plus I forgot to mention my need for a VESA mount option ;-(

Then again, the review seems to confirm what I'm hoping for, and I've found a 17-inch candidate:

https://www.amazon.com/gp/product/B083XKS6NB/

I have the i7 version of that series of NUC as my primary navigation PC and have one monitor connected via HDMI + USB for touchscreen, and a secondary one connected via USB-C and they both work great. Make sure you upgrade the firmware/drivers/BIOS as there were a bunch of fixes (at least for my version) with the USB-C port that sounded like they would matter - you know how hardware vendors are....

I can't find the model of monitor I purchased, but it was a bit bigger than what you're looking for I think - 19-23" - the one you linked above looks nice!

Thanks, Steve, and were you getting touch control on the USB-C screen?

It works! I bought a $219 Wimaxit 15.6-inch touch screen -- https://www.amazon.com/gp/product/B07YXP683D/ -- and it is working as a touchscreen 2nd monitor just from the Type C output of the NUC7i5BNK. Well, it's almost a one cable operation. At first, it powered up but was just acting like a big touchpad -- no display -- until I tried using the screen's 2nd USB C port to give it added power. 

I can run the second monitor as an extended screen but mirroring suits my intentions. The touchscreen will VESA mount at Gizmo's helm for TZ PC and other navigation uses and I'll use the big nontouch screen already at the chart table for planning and general computing, usually only powering up the one that's needed (though both screens might make sense when a mate is helping with the navigation).

This is all a little theoretical until I actually use it in earnest -- like will the touchscreen be too dim sometimes, too bright other times? -- but seems slick at least in concept 😉

@ben-ellison so sorry I didn't see this! Not sure why I didn't get a notification, or maybe I just missed it? 

Yes! I am getting touch screen, but like you, I have had to provide secondary power via another connection. Theoretically it should not require this, but the specs on the NUC aren't totally 100% convincing that it can provide enough power....

Glad you got it working! That's very similar to what I have right now. NUC + big Planar touch screen at the salon driving station running TZ Pro, 2x TZT2 12" MFDs at the flybridge helm where I drive from the most, with a new portable monitor there mirroring TZ Pro.

The USB developers forum driven mostly by Intel, Apple, and Google, have been trying to unify the connector world for a long time and in theory it should culminate in the next few generations of USB3. There have been many interoperability issues with combinations of USB, DisplayPort, Thunderbolt, and Power Delivery. The "cables" - which now have fairly complicated computers in the connectors - are getting to be a nightmare to mix and match. Glad you found a combo that works.

Keen on hearing more!

Everything I described at the beginning of this thread is working fine so far on the boat, though I didn't get to use it a lot by the time I'd redone both helms last season. But I can report that I rarely used the bigger monitor already installed as the Wimaxit 15.6-inch touch screen is good enough for planning, navigation, and other PC chores, either touch only or with that wireless keyboard. I do have a lot of photos and plan two more helm ergonomics entries.