Could you please let me know the BIOS version installed? I would also recommend checking the BIOS jumper settings, make sure that you have 1-2. See here for the settings http://www.intel.com/content/dam/support/us/en/documents/boardsandkits/NUC5i7RYB_NUC5i7RYBR_TechProdSpec04.pdf (page 47-48).
Thank you for the reply.
To your request:
Bios version: RYBDWC35.86A.0358.2016.0606.1423
Bios jumper is set for normal operation per the spec.
I connected using VGA-to-miniport with the same issues. There is no Intel NUC splash screen displayed. Video becomes "live" when Windows is running at my desktop view.
I have Windows 10 home, 64-bit version.
I guess I will go buy a new monitor anyway.