Today, I tried a different video card in the quest to finally solve the Oculus HDMI to Nvidia problem. Few days ago I detailed my difficulties in obtaining an image to both the DK2 and Consumer Rift with one of the latest Nvidia cards the GTX 980 Ti.
This card booted up into Windows just fine with both HDMI and DisplayPort. When the Rift is turned on, and the Oculus software is displayed the Oculus Rift remains black.
To make this a little easier, I added an HDMI extension cable into the mix, so it is simpler to unplug the Rift and Plug it back in.
Manually unplugging and plugging in the HDMI is not the ideal situation but, at least, workable. Please note however that the HDMI to DVI/DisplayPort still works just fine.