In another tale of hardware not quite working as expected, there are reports that the Nvidia GeForce GTX 1080 and 1070 Display Port doesn't work with the HTC Vive virtual reality headset. Nvidia markets both the GTX 1080 and 1070 as offering "innovative new gaming technologies and breakthrough VR experiences," so to have this compatibility problem exist, with the best selling PC HMD, seems like a bit of a blunder.
Tom's Hardware details the case of one user who wanted to hook up his HTC Vive to the Nvidia GeForce GTX 1080, using the optional Display Port on the HMD's link box, as the HDMI port on the graphics card was already in use. Such a configuration was known to work with the previous gen GTX 980 Ti but DP connections don't work with the Vive on Nvidia's new GTX 1000 series cards. Tom's Hardware reporter, Kevin Carbotte, confirmed that the DP connection issue was present on the GTX 1080 cards in his workplace labs. You can see the error messaged generated when trying to hook up a GTX 1080 to a DP port below.
The issue of the non-compatible DP port was raised in Nvidia forums about a month ago and garnered an official response of "We are still investigating this issue". Testing various driver versions doesn't provide any respite. However any fix, if it comes, would likely be via some driver software update.
If you use HDMI for your primary display and are interested in purchasing an Nvidia GeForce GTX 1080 it is suggested you look at something like the Asus ROG GTX 1080 Strix with twin HDMI v2.0 ports provided - with VR connectivity in mind.
A Founders Edition, left, Asus ROG GTX 1080 Strix, right
Further reading about Nvidia GTX 1080 and 1070 Display Port incompatibility with the HTC Vive can be found via Reddit, and on the official Nvidia forums.