Not too long ago, ATI dropped support for my video card (ATI Radeon X1950XT) from the FGLRX driver. When this happened, E17 reverted to mirroring my two monitors. GNOME, for whatever reason, seemed to work just fine. For a while I just worked in GNOME, but eventually I got curious, and decided to determine what was up with E17. Since repeated web searches yielded next to nothing, I figured it had to be something weird with my system. It took me a while, but I finally figured out how to turn dual head back on the way I wanted. It all boils down to this one handy command:
$ xrandr --output DVI-0 --mode 1600x1200 --pos 0x0 --output DVI-1 --mode 1600x1200 --pos -1600x0
This command sets the resolutions for each of my two identical monitors, and sets the position of DVI-1 (which happens to be “on the left”) to be 1600 pixels (or one screen’s worth) to the left of DVI-0 (the monitor on the right).
I’m reasonably certain that the gnome-display-properties command basically just does the same thing, but for some reason it was ineffectual when being run from within E17.
