Encore requires a couple of different types of DVI cables for connection of sources to a router or directly into Video Processor units, and for source link and program link between Video Processors for widescreen or widescreen preview applications.
Program link and source link cables, which are interlinks between one Encore VP and another, need to be DVI-I Dual Link cables – DVI cables whose connectors are fully populated with the maximum possible number of pins. This is due to the fact that Encore needs to be able to send analog, DVI, SDI, sync, and overlap information from one unit to the next.
The DVI source inputs on an Encore video processor only support DVI-D, with the exception of the unscaled downstream key and background inputs, which can be configured to accept analog or DVI signal.
To connect sources to a Matrix PRO DVI router, and to connect the router outputs to the Encore video processor inputs, you should use DVI-D single link cables.
To connect analog Downstream Key (DSK) or background sources directly to an Encore VP, you need analog to DVI-A cables (i.e. HD15 or RGBHV at one end, and a DVI connect which carries the analog signal at the other end).
Wikipedia has a fairly comprehensive article on DVI signal and connection types should you require more information on the differences between DVI-I, DVI-D, and DVI-A.