I' m having the same issues with the same system 5i5RYH and a Dell P2412H monitor. mini HDMI to DVI
Windows 10 Pro x64.
Did all the Windows updates and Intel updates (new BIOS, Intel Driver Update Utillity) but still can't work after wake up.
I put the system to sleep via the start menu -> power -> sleep.
LED on computer starts flashing red (as set in the BIOS), so comp is in S3 currently.
After a couple of minutes I move my Wireless Logitech M705 mouse and the LED on the computer turns blue.
But no screen, and also when I push caps lock on my Wireless Logitech MK700/MK710 keyboard no indication on the keyboard display is shown, so I think there is a USB issue here.
I have another similar system with (still) Windows 8.1 on it, I have exact the same BIOS and power saving settings. This system works fine comes back perfectly, so I think the issue is the WIN10 drivers for the NUC.
Any idea on Intel side???