Well I've got a X38 + 4870 Crossfire setup and that leaves me with less space than you (aka 1 slot vs your 2 slots in the middle) and my Xonar works just fine there. So yes it can be done. Heh in fact your card looks very similar to mine so the sound quality will be amazing.
From the 2 evga 780i boards i just checked out you dont need to put the PCI card between them. If your using PCI-e16x slots 1 and 2 there is a PCI slot at the bottom of the board. If your using PCI-e16x slots 1 and 3 you shouldnt have a problem putting it in the middle PCI slot.
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Reply to chookman
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