I'm not sure of the other technicalities, but control software for two synchronized outputs out of one Windows PC's dual head graphics card exists. Have a look at AvStumpfl's Wings Platinum 4
Pro version -
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Dualdisplay for panorama and 3D projection
Softedge panorama or 3D stereo shows can be run on one computer if you operate two video projectors on one graphics card with two outputs (dual head). This requires only a moderate amount of hardware although the dual-display solution will be rather pushed to its limits when it comes to complex shows compared to real multi-display technology with networked computers (eg. The Wings Platinum 4 Multi-display version)
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They have a demo download is available:
http://www.avstumpfl.com
Thomas Leong
