Monitor Won't go above 60hz with Display Port

[JamieMalburn]

I have a display port to hdmi cable in my main monitor (Benq XL2730Z) and a hdmi in my second monitor (AOC 2757). I have to keep it this way otherwise for some reason both my monitors stay blacked out and do not display anything but a black screen but are clearly on because its not the same black it is when turned off. It is hard to explain but the monitor displays a black screen and isnt off. Because of this setup my monitors look like this, (1 being the AOC and 2 being the Benq)
http://imgur.com/a/RAnHD
My BenQ will not go above 60hz when it is a 144hz monitor and also will not go above the resolution 1920x1080 when it should be able to go to 2560x1440. I am unaware of why this is and also seek an answer to the issue i stated previous to the resolution issue about why i cant have the hdmi cable go to my BenQ and the display port to HDMI cable to my AOC. My specs are below.

i5 4690K
EVGA GeForce GTX 970 SC GAMING ACX 2.0
16GB DDR3 1866MHZ HyperX Fury White
MSI Z97S SLI KRAIT EDITION

 

[Matthew Keeton]

I think this link will at least help to diagnose your problem. http://www.tomshardware.com/forum/id-2029797/stuck-60hz-144hz-monitor.html

 

[Calvin7]

(AOC 2757) does not support a 144Hz refresh rate.`

 

[Matthew Keeton]

Pretty much what he said. /\
l

 

[JamieMalburn]

Im looking to get the 144hz on the BenQ but it won't allow me.