I have a dual-G5 running 3 monitors - a 20 inch Cinema and a 17 inch Studio on the Apple (ATY, RV350) AGP card and an CRT on an older (ATY, Rage6) PCI card. When running the Cinema display at 1680x1050 with the Studio at 1280x1024 the disk icons are gone from the Cinema desktop as are SOME of the other desktop items. For example, other mounted device will not appear but other items dropped to the desktop MIGHT appear. All desktop items appear when opening a new Finder window. The dock is at the right of the Cinema display and works fine. The mouse cusor operates in all the Cinema territory; however, the ~1 inch vertical strip on the RHS of the Cinema display will NOT support any icons. That is if you move an icon into that territory, it snaps back. IF I lower the resolution to 1344x840 ALL icons appear and ALL screen surface is accessible! This or related BUGS have been reported to APPLE and have been present since arrival of the Cinema display while running under the 10.2.8 on a dual-G4 before moving to the G5. Thus this is an operating system bug.