Thanks for the suggestions! Actually, I always download the latest OS drivers for the OS I am installing prior to installation. Remarkably, after the Windows 10 install, Device Manager showed no missing or malfunctioning drivers. I went ahead and installed every driver I downloaded from Intel thinking that they might be better or more complete than the basic Windows drivers. One of the Intel drivers wouldn't install with a pop-up message saying the OS driver was newer. I can't remember which one ...duh. I'll check and see if the installed chipset driver is newer than the one I downloaded and install it if newer.
Since you stated the ssd can not be a possible cause, I'm thinking I'll probably have to re-install the O.S. to fix the problem. Not looking forward to that because I have already installed Ubuntu in UEFI in a dual boot on the second hard drive and will probably have to re-install it too and it works fine compared to windows 10.
I found the problem......I think! I re-installed Windows 10 but still got frequent power surge warnings....everytime I woke it from sleep as well. I remembered a problem I had with USB ports on a previous NUC pc that caused the wireless keyboard and mouse to malfunction and the cure suggested was to unplug the wireless receiver and plug it into a USB extension cable. Just on a hunch I tried that with the NUC5i3RYH that was acting up and EUREKA.....I haven't had a power surge warning for two days...even when I use all 4 ports, including one connecting my HP monitor with 4 USB 3.0 ports.
I think Intel still has work to do with either the NUC firmware or chipset driver. This shouldn't have happened if the NUC was working right. I am using the latest downloads for Chipset, MEI, wireless, CIR drivers for Windows 10.