Could this be power related? You may want to check your system’s power needs and the power supply wattage.
You may also want to check if there is a firmware update for your graphics card and if the processor and memory are running at default values.
If available, you may also test with a different graphics card.
So I figured it out.
When you change memory amounts on this MB, you have to reset the CMOS for use with an external video card. I discovered this by accident as I attempted every possible combination of things to try and fix it since I knew both memory and video card were known to be good.
Joe, your suggestion was also proffered to me over at the EVGA site, but as I pointed out to EVGA, the addition of 2 sticks of memory simply don't cause enough power drain to seriously consider as the culprit, and in any event the 800W power supply is more than big enough to handle it. However, I appreciate that you took the time to reply as the issue was quite frustrating.
Since the EVGA nVidia GTX760 is quite a common mid-to-high-end video card, I consider this part of the buggy nature of this motherboard. So if you have this motherboard (or it's variations) and you're changing memory, you'll want to reset the CMOS as you boot up, and be prepared to switch back to using the built-in graphics card to reset the CMOS.
But for now, I have Windows 8.1 running with 32GB of memory with an add-in video card.
Thanks everyone who offered support or at least read my post.