I have a Dell u2713h external monitor, running Windows 7 Ulitmate, with quadro k5000m nvidia graphics card. I have a problem when using the external display and operating the Revit 2013 program. When you left click an element or line in the field it automatically moves to a new position usually up on the modeling field. This does not occur when the window is moved to main display. I have tried to lower the resolution of the 2569 x 1440 resolution external monitor being used in extended desktop mode, but this does not resolve the issue. I have contacted Dell, Nvidia and both insist that the problem is not with their hardware or software, however I suspect this is an acceleration issue or particular setting that need to be changed. Please help as this issue is extremely disfunctioning for creation purposes.