Adding second monitor cable stops boot

English Install/Boot/Login
1

-I have one Dell 24" monitor set up and working through an HDMI cable > GeForce GTX 980 Ti. Nvidea X Server Settings is installed (and I think was the ap that got my Dell 2408 working well).

-However, when I try to boot with a second monitor (same kind), Displayport cable to graphics card, the computer simply doesn’t boot. Black screen, dead fans.

-If I plug in the second screen after the BIOS, Leap sees it, but in Configure Desktop calls it DP4 and doesn’t give the option of configuring it like monitor 1.

-The Nvidea software isn’t any better.

Any help most appreciated.

2

That shouldn’t happen. Perhaps a defective cable? If you didn’t already, try testing the cable in another system, id available. I presume your system is a desktop, see if the cable works as the only display, also if there is a priority setting in BIOS (there should be).

Disclaimer: just guessing, I don’t have a DP display here to play with.