Weird problem I can't trouble shoot with the nuc 5i5ryh. I have a mini display port to HDMI converter on the nuc and so a normal HDMi cable connecting the converter and my quad res Acer monitor. Problem is that when powering the nuc, there is nothing displayed on the screen but when I power on the nuc with the HDMi disconnected from the converter, wait till I think windows 10 has booted, then plug the HDMi cable back to the converter and now it works fine. I have updated Intel graphic drivers and bios. It works the same on different monitors. I do have a mini HDMi to HDMi cable and that works fine but I'm working on a case mod that required I have a Converter. I could use a mini HDMi to HDMi converter but I don't want to spend $10 then find out it works the same as the Mini DP to HDMi converter. So if anyone's got possible solutions Id appreciate it tyvm.
It seems related to the converter you have, Intel recommends using straight connections in order to ensure the connection between the components. You mentioned that the mini HDMI to HDMI cable worked fine, so this is indicating that your converter is not working due compatibility issues.