OK, at risk of hijack (though useful to the OP i'm sure), what do you get out of the Sapphire Vapor?  Scrypt i assume?  I've tried everything with one and i cant get above 560 KH/s (was ~600 MH/s under SHA256 for raw Bitcoin).  I am using a full width riser because it wouldn't fit in the PC (HP office box, free and with 4GB) but not sure why that would make a difference.

as for mixing cards, everyone says no problems, but i found the main card dropped significantly in output when adding a second.  use of un-powered risers might be an issue here, though i still don't get why power isn't transferred through the riser if its available and required by the card (which should surely just require the PSU input).

Back to the OP, in cgminer you just have to separate the settings for different cards using " ," between values, as they'll probably have different optimal clock and Intensity settings.