I have problems when connected to a projector to mirror my desktop onto wall-size screen in my classroom. Seems to have similar "issue." As I go back and forth from Mac OS X to Win XP in Parallels, it often cannot discern what resolution I'm at and the PC in particular randomly (sporadically, but not always) tries to refresh at diff res. Is this a display res problem or a refresh rate issue? (Or are they the same thing, in this context...) Sometimes when power save kicks in, the same problem occurs when I move the mouse again to wake up the MacBook Pro. Cannot tell whether cause relates to projector having lower max res than MBP. Projector useless at widescreen 16:9 ratio -- it's worse then. If the PC is suspended, sometimes same thing when it wakes up. Cannot discern yet if it makes a difference whether I'm in windowed mode or coherence. I could be more specific if this maddening scenario always occurred in same pattern/sequence.
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