Thank you for contacting Intel Communities.
I am sorry to hear you are having flickering issues with your Intel® NUC. Can you please try the following to see if the issue persists?
Install the Intel® Graphics Driver for Windows* [15.45] Version: 18.104.22.16864 (Previously Released) Date: 5/3/2017
Check if the Windows update KB4022716 is installed, if yes, please uninstall it.
Please let me know how it goes.
Thanks for answer. I have tried to uninstall KB4022716 yesterday, I found in another thread that it can cause similar issue but it didn't help me. I was testing it along with 4678 driver version.
Today new Windows Security Update KB4025342 has been installed and I think it replaced KB4022716 bacause I don't have it in system right now. Anyway I uninstalled latest graphic driver, I let Windows to install automatically another version and I uninstalled it again, I kept repeating this steps until I had Microsoft Generic Driver. Microsoft Generic Driver had only one resolution 3840 x 2160 @ 64Hz and I had no flickering issues, of course no hardware acceleration either.
I installed Intel® Graphics Driver for Windows* [15.45] Version: 22.214.171.12464 (Previously Released) Date: 5/3/2017 and my flickering issue is back. I also tried to install the driver from Microsoft Update, I'm not sure what version it was but I'm pretty sure earlier then 4664 and I also have flickering issue.
I've updated BIOS, restored default settings and it didn't help, installed latest Graphic driver and still flickering were there, but...
I started playing with aspect ratio, changing options one by one and when I went to last setting, flickering stopped. I restarted computer and still is OK. So fingers crossed. I will check tomorrow if the issue is gone forever, is late in Central Europe now.
My current settings: