I don't think this will be a problem -- that card is supported in neither Ae nor Pr, so they should not even try to use it.
The only thing that may be a factor is OpenGL-accelerated effects in Ae (like Magic Bullet Looks, Optical Flares, Element 3D, FreeForm Pro and ShapeShifter AE). I'm not sure what the rules are for which card to use in a multi-GPU situation -- whether they always use Display 1, or whether they use the card the main interface is open on.
Walter Soyka
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