I have been having trouble with my openGL viewing over the past few days and after re-installing drivers and application software I have narrowed the problem to having dual monitors set up. If I open an archicad file while both monitors are set up, I am unable to use openGL in the 3D window. If I dis-able my second monitor I am once again able to use openGL in the 3D window. After the file is open I can re-enable my second monitor and work without problems. This issue has appeared recently and I had thought might be related to windows service pack 2, but I have not confirmed this. Very strange behavior and I am curious if any others have seen anything like this. The two monitors I have are different from each other and perhaps this is part of the problem. One is a flat panel display and the other a standard monitor.
