I am running Linux Mint 17 with KDE and display drivers from Nvidia. I've configured the display settings using nvidia-settings, and when I first start up everything appears to work correctly.
However, when I log in and KDE is loaded, it does something to my display setup which turns off one of my three connected screens. Using the KDE Display settings I am unable to turn the screen back on, but restarting the session and returning to the login screen shows the login dialog on this screen as intended.
How do I stop KDE from messing with my screen setup? Alternatively, why is one of my monitors getting turned off? FWIW, the monitor affected by this is connected via HDMI while the other two that keep working are using DVI.