MBPR Not showing 3440 x 1440 option for external monitor

[Aksta]

I am trying to connect my new Acer XR341CK bmijpphz to my 2012 MBPR retina but I cannot see an option for 3440 x 1440 under scaled resolutions. The maximum it will let me set is 2560 x 1080.

I am using a mini DP to DP cable and have a tried a few of them that I had lying around but I am still getting the same issue. Does anyone have any steps I can try to get them working. I have checked latest updates and tried restarting..

Any help is much appreciated

 

[xraydoc]

That's close to a 4K resolution; can the 2012 MBP support it?

 

[Aksta]

I would assume so, I have it working using a custom resolution using switch res X but it is limited to 40hz. Thats fine for now but I would have thought there would have been a way to get it work natively.