I'm running a dual-screen setup on my main PC, with a 28" monitor connected via DisplayPort and an old 19" screen connected via DVI. Unfortunately, a lot of older games seem to insist on trying to run fullscreen on the 19" monitor.
Sometimes I can coax it into using the main display by fiddling with settings, or by using XRandR to deactivate the second monitor. However, other games will insist on using the DVI output regardless of whether that output is currently enabled via XRandR.
Is there some configuration trick I'm missing that will ensure that games will default to using the DisplayPort / 28" screen?
I'm running Kubuntu 14.10 (w/ Plasma5 Preview) and an NVidia 780 Ti w/ NVidia binary drivers.