Thank you for contacting the Intel community.
In this case, we will need a Debian user to provide us some help to help you with this issue. I’m sure somebody will drop by and give some advice.
Please bear in mind that Intel only tested this unit with Windows® 10 and for that reason there is no much support we can provide based on Linux* support, in this case you will get better support at the Linux* community, also you can try posting this issue here:
Thank you. Any answer is appreciated. Have posted in Debian and other forums too, but it is not as easy as you might think! Sorry Intel only supports Windows 10. I can understand it is hard to support every possible Linux distro! I sure would not be able to.
But Debian is pretty big, as is Ubuntu which is Deb based had has much in common, so maybe some compassionate Debian user will take pity here. You see, this is the only forum I know specifically focused on NUC6CAYH so please bear with me.
Who knows, I bet there is even an Intel genius who secretly likes Linux who might slip me a clue...
Any, the wifi issue should not be too difficult. I had a NUC5i5 that I got the wifi working so it is mainly a matter of knowing what the Linux driver is for the hardware.
It seems that Debian user will have to be me who posted the question.
Anyway, the tearing I experienced was resolved by
1. Updating the kernel version to 4.12
2. Reinstalling the xserver-xorg-video-intel driver and being sure the intel driver and not modesetting was being used by running inxi -G in a terminal.
3. Created the file 20-intel.conf including the following code:
Identifier "Intel Graphics"
Option "TearFree" "true"
4. Since inxi -G returned
GLX Renderer: Mesa DRI Intel HD Graphics 500 (Broxton 2x6)
I installed the Broxton related files from https://01.org/linuxgraphics/intel-linux-graphics-firmwares . To be honest, I don't know if this helped or not. Nor am I sure if each step above is absolutely necessary.
In any case, the tearing issue was resolved.
Sorry, I posted the wrong answer and have sense posted that reply elsewhere where it was relevant.
The wifi issue was embarassingly simple to resolve. It was one of those cases of missing the forest for the trees. The iwlwifi firmware was in fact working well with the NUC6CAYH. The driver first looked for iwlwifi-3168-29.ucode, then 28, then 27 and so forth, none of which was found, but finally hit on 22 and worked well.
The problem was that WICD which I was using simply didn't register the wireless interface. Once I entered it manually everything worked fine.