I was experiencing a huge amount of blower/fan noise on my NUC6i7KYK.
It began 14 months after I purchased it, the fan blades inside were hitting the casing.
This is how I fixed it :-
First you must remove the bottom cover plate.
Now remove the black tape covering the blower/heat sink fins ( keep the sticky side clean from dust
you will need to put it back).
The blower is not connected to the fins.
There are only 2 screws holding the blower to the chassis, one is at 11 o'clock the other 5 o'clock.
Remove these 2 screws and keep in a safe place.
Now gently pry the blower with a thin screwdriver, it will come out easily.
Hold the blower by its sides only, not by the top or bottom.
Now clean the fins and the blower with compressed air or a small soft artists brush.
Hold the blower so the underside is uppermost, you will see a power cable, 3 thin metal arms
connected to a central disk with a white sticker on it.
Now you must find a coin the same size as the sticker (not bigger, must not touch the cable),
I live in England so I used a one pence coin.
Place the coin on a flat level surface, center the blower over the coin, sticker side down.
Press the blower down (hold by edges only) onto the coin for a few seconds, the coin will
level and balance the fan motor and lift the 3 metal arms a couple of millimeters.
The rotating blades inside will now not hit the casing.
Refit the blower and screw it down ( do not overtighten ) put back the black tape.
Refit the bottom cover plate.
I hope this method works for you, it worked for me and my Skull Canyon is quiet as a mouse
now even when playing games.
I think the NUC6i7KYK develops the noise problem because over time dust accumulates
on the fins and the unit becomes very hot thus distorting the blower case or spinning
blades on the motors spindle.
Thank you for joining this Intel Community and sharing your experience fixing the noisy fan issues on your Intel® NUC. Your feedback is highly appreciated.
Hopefully, other users will benefit from this useful information.
Intel Customer Support Technician
Under Contract to Intel Corporation