I've been struggling to solve this for a few hours now. I have a workstation running ubuntu 14.04 and I've installed openbox and I log in using that by default. I have two nvidia quadro k2000 gpu's with each DisplayPort plugged into a monitor in landscape and the DVI port on GPU0 plugged into a monitor in portrait. I'm trying to add another DVI monitor in portrait mode to the DVI on GPU1, but here's where it gets weird. If I set the new monitor to be in landscape mode (using arandr), everything works fine. As soon as I put it into portrait mode, its as if the computer loses track of which one is which and renders half the frames from the other portrait monitor on each. All the graphical output from each overlaps and never redraws unless I do something active on that monitor. Its really quite strange.
Can anybody help?
BTW I've reproduced in XFCE and Unity
EDIT: Here's what it looks like, that window is on a the other monitor and I'm moving it around. https://i.stack.imgur.com/qbxdJ.jpg I've tried nvidia-settings but it crashes every time I try to save. Any suggestions as to what settings I'd need to use on nvidia-xconfig or nvidia-settings to get it working again?