The HyperX memory (HX421S13IBK2/16) work good with NUC, so compatibility should not be a problem. I'll suggest try the following steps:
1. First try to recover your bios BIOS Recovery Update Instructions for Intel® NUC . The latest bios version is 0046. Download the .bio file from here: Download BIOS Update [BNKBL357.86A] . There are two bios recovery methods. The preferred method is with the security jumper removed, and it is executed automatically. If you prefer, you can use the Power Button method (press F4 after you see Power Button menu). Push the power button and hold it down for 3 seconds. The system will emit three short beeps from the front panel (FP) audio port (if you have connected speaker), then you shall release the power button. The FP power button LED will also change from Blue to Amber when you can release the power button. You shall release the power button before the 4-second shutdown override.
2. If bios recovery didn't help, try using just one memory module at a time, swapping it between the upper and lower memory slots.
Hope this will help
Thanks for the tips
I Have try to switch SODIMM modules and try to use only one module at a time. No difference.
I removed security jumper and installed USB flash with 046 bios file in USB port.
NUC didin't even try to boot. after pressing power button (3 sec or longer).
After putting security jumper back to 1-2 (normal mode) NUC try to boot and flashed
power button light few time and shut down. Just like what happened earlier.
I don't have any laptop to check the SODIMM modules and my workstation doesn't
support M.2 ssd module so I can't isolate possible hardware problem with these components.
Since you did every think what I ask for without result, I think that in some case clearing CMOS by disconnecting for few minutes the CMOS battery may solve the boot problem. I believe it was Scott's intention in his post #4 above. The CMOS battery and its connector are located on the top side of the NUC board. In order to get access to the battery connector, you need remove the bottom cover and then remove the board after unscrewing the holding screws. Before doing this remove the memory modules and SSD. If you fill capable to do this, try this.
Unplugging battery was right thing to do because then I have to take apart whole NUC.
After I take the mainboard out of box I notice that the whole "Thermal solution" was loose.
My "no booting" problem was not electrical or from software.
MY PROBLEM WAS MECHANICAL AND DUE TO LACK OF CONTACT BETWEEN PROCESSOR AND
"THERMAL SOLUTION" I WAS HAVING THERMAL THROTTLING AND NUC SHUTS DOWN RIGHT AWAY
AFTER BOOTING (2-3 sec after pushing powerbutton).
Allso the metalplate under CMOS battery was loose.
Intel. Your subcontractor who is assembling NUCs have major quality control problem.
I had to disassemple the "thermal solution" and blow it apart and reassemple it.
I have never earlier seen so bad quality cooler in any prebuilt PC (or selfmade ones)
I agree with you absolutely. Many new and strange problems we see in this forum with the latest NUC new line. NUC is not some cheap PC. Specially NUC7i7BNH is not cheap at all. After such findings Intel shall not answer as usual that "we are glad that your problem is solved". Intel shall make an investigation and improve the assembly line. Using the Serial Number of your unit, may help in such investigation.
I am not very keen to sent NUC back to Intel because it is now up and running. OS and all software installed.
I have activated Win 10 OS, so I would have to reactivete it with the new NUC .
I bought the NUC from Mindfactory Germany and now the NUC is in Helsinki, Finland.
Main problem was three "legs" that connect cooler to motherboard. The "triangle" they made didn't met holes in motherboard. I Have to take them apart of the cooler and
I had to make some mechanical "adjustments" (sandpaper) and then I glue the "legs" to the motherboard. After that I attached cooler (and adding some Noctua thermalpaste
between prosessor and cooler). Now I have to trac processor temperatures for few days.