This message was posted on behalf of Intel Corporation
Hello Jinsung Kim,
Thank you for contacting Intel Support,
I understand that you are having performance problems when playing HDR videos on youtube since the video lags, I apologize for any inconvenience this may have caused.
Regarding this problem, I actually replicated it with the equipment we have here and I was able to play the provided video at 2160p 4k 60fps HDR. This means that the unit should be able to play HDR videos just fine. I used the following settings:
1) HDR: On
2) Windows 10 build 16299
3) Graphics driver: 4849: https://downloadcenter.intel.com/download/26947/Intel-HD-Graphics-Driver-for-Windows-10-for-Intel-NUC-Kit-NUC7i3BN-NUC7i5BN-and-NUC7i7BN?product=95066
4) Microsoft Edge. https://www.youtube.com/watch?v=1La4QzGeaaQ at 2160p 4K HDR.
5) RAM: 8GB, initially had 4GB and it was causing some lag which was fixed by increasing the RAM to 8GB.
I hope you find this information helpful.