Recently purchased 2 evga GTX 980 SC cards and successfully installed into a new build based on an Asus X99 Extreme 11 motherboard running Windows 8.1.
 
As I did not yet receive the Acer XB270HU monitors, I set up the rig against an Acer H234H (DVI connector) I had on-hand and it worked without issue. Install went smoothly and the cards work beautifully in dual SLI mode.
 
Yesterday I finally received the new monitors. Got them out of the box and setup. They ONLY connect via DisplayPort connections. I wired them to the first (top left most) displayport connection on each card. When I go to power on the system, I get the "No signal detected" message - then nothing.
 
If I connect back up the DVI monitor, works fine. If I try to connect up just one of the displayport monitors (tried both individually), same thing - "No signal detected". I have the latest NVidia drivers installed (via the GeForce Experience app). Like I said, everything works just fine with a DVI monitor. 
 
Do I need to use special cables to get these cards to work with this monitor? Anyone here have any advice on how to troubleshoot this problem? These are the first displayport monitors I've ever owned, so not sure if there are certain BIOS settings I need to enable?
 
Thanks in advance for any assistance. 
 
 

 I called EVGA and the guy told me the no-signal issue is a handshake problem, no question about it (which, I actually think is accurate). He then went on to tell me there is nothing EVGA can do about it because it is not, specifically, an EVGA problem (which I thought was odd since I have an EVGA card). But, then I asked, if it is an EDID issue, wouldn't / couldn't a vBIOS update solve the issue? He said yes but didn't offer me the new vBIOS nor the one from Feb. He just said it will not help and I should use a monitor since they have a standard for EDID. Not a solution, but the guy was less than helpful which is sad because I went with an EVGA card due to what many say is excellent USA CS.
 
Concerning your specific issue, if it is not an EDID issue, I think there is some sort of initial setting that kicks in. I did the same as you, went to a TV after installing from a monitor, and have the same issue (although over HDMI). This particular issue is all over the internet and I kick myself for not being prepared to address it. What will likely happen is that someone at EVGA will provide you a vBIOS, same as I asked for and was told, in no specific words, was not available / going to help.
 
If worse comes to worse, you can buy a "3ft 28AWG DisplayPort to DVI Cable - White" from Monoprice and see if it works. They are great re returns, so worst case scenario is you are out about $5 for shipping costs. You're not going to lose much going over DVI for the time being, although obviously this would not be a long term solution.
 
It is very likely not a BIOS issue (I assume you were referring to the motherboard BIOS). It is a setting in the vBIOS of your GPU. Check your vBIOS revision via GPU-Z or some other software tool and compare it to the newest ones available, because in Feb. (or thereabouts) there was a BIOS revision released that helped many with this issue, although I do not recall if it was for the 970 or 980.
 
Can't provide links, but search this forum for the following: "New BIOS for GTX 980SC ACX 2.0"

I got a acer xb280hk today, along with image flickering and black bars pooping up and disappearing instantly again.
After I contacted support, they gave me the new BIOS. After updating it however, I'm still confronted with the same issues.
My current BIOS version is 84.04.31.00.83.