HD 7970 cannot run higher than 1920x1200 resolution on Cinema Display

[pleasehelp20]

Hey everybody

I've been doing a lot of research... but I couldn't find anything so far!

My Apple Cinema Display 27" monitor works perfectly with my macbook at its native 2560x1400 resolution... but when I plug it into either of my two mini display ports of my Radeon HD 7970 I cannot find a higher resolution than 1920x1200!!

Sometimes I get a message saying there is a Display port link error. I'm running on windows 8, but I had the same issue on Windows 7!

Please help me fix this, it would be so dumb to buy dual link dvi to mini DP port just because the standard mini DP port doesn't work!!

Thanks!
Regards

 

[Kippa]

Just had a look on a shop and says that the maximum digitial resolution for the 7970 is 2560 x 1600, so it should work resolution wise

 

[VulgarDisplay]

Make sure you bought the correct display port cable. If its like HDMI, a cheap knock off cable may not provide enough bandwidth to display that resolution.

 

[3DVagabond]

Yes, it should work fine. It's not normal for the DP to only go to 1920*1200.