Comment # 13 on bug 908747 from Bruce Mallett

Thanks everyone.  I can get by with the xrandr mode business and now have
something that works after putting the following in my .bash_profile
(appropriate place?):
  if [[ "$DISPLAY" = ":0" ]]
  then
    xrandr --newmode "2560x1440R"  241.50  2560 2608 2640 2720  1440 1443 1448
1481 +hsync -vsync
    xrandr --addmode HDMI1 2560x1440R
    xrandr --output HDMI1 --mode 2560x1440R
  fi

Works and gets me a proper dual monitor desktop.