dual monitor issues in 11.2

with KDE everything works fine (both monitor show their configured displays correctly), however oddly with gnome when i try and setup dual monitor display, i get blank screens on both monitors, however on the display 0 on the left side there is a full column single pixel width green strip… the rest of display 0 and 1 are blank, however my mouse will move around both display correctly. seems pretty odd, anyone have any ideas?

fyi, it is a desktop effect issue… when dual monitors are setup as two seperate displays, it does not go so well… single monitor desktop effects are fine. dual displays work fine without effects…