Displays Blurry text on secondary monitor.

Just set up a secondary monitor and noticed that the clock was blurry, moving an open GPU-Z box over to the screen it to is blurred. I have it connected by DVI should I switch to HDMI, or is there a setting I am missing?
Second monitor is a Dell U2711 with a resolution of 2560 x 1440, primary monitor is a Dell U3415W with a resolution of 3440 x 1440.

Edit.It looks like a Windows 10 scaling issue which was supposed to be sorted in the Creators update.By changing the resolution to 1360 x 768 makes stuff readable but is not ideal.

 

Check its not applying any under/over scan at the native resolution.

Sent from my HTC One_M8 using Tapatalk

 

How do I do that mate?

 

Is it just a single or dual link DVI cable? It needs to be dual link.

 

You may have hit it.

Edit; Only had one dual DVI in my massive bag of video cables and that gave no image, must be faulty, bunged a HDMI in and all is well.