Thanks for sharing this behavior with us. Would you please check on BIOS, which is the BOOT order on your NUC?
Please check if “boot from LAN” is the first in the list. If it is, please change the order and make sure it is the last boot option.
If you enable Ethernet, does the NUC works perfectly?
Boot from lan is not in the list for efi and is second in the list for legacy boot. I disabled legacy boot and I still have the same behavior.
The Nuc works fine with ethernet enabled but fails to restart and wake from sleep with it disabled.
Have you try to update the BIOS to the next available version?
Also update the network driver to the latest one?
If the issue persists and if the NUC is still under warranty please get in touch with our Warranty Department so they can help you to replace the unit: http://www.intel.com/p/en_US/support/contactsupport