I have a 27" screen which is connected to my mid-2012 MacBook Pro retina through a HDMI/DVI-D (HDMI on the MacBook Pro, DVI-D on the screen).
Before I was using a adapter DisplayPort+USB/DVI-D and I was able to get 60Hz refresh rate.
Now with the HDMI/DVI-D I have only 30Hz.
Is there any way to change (by forcing?) refresh rate to 60Hz?
Or is it a hardware limitation?
NOTE: I can't change the Refresh Rate value from System Prefs, the menu is disabled and the value is set to 30Hz.
EDIT: Here's the System Prefs window