you simply can't cram three DVI connectors on the back of a single card.
Not directly no, but there are ways to do so.
3 hdmi connectors with either short hdmi-dvi patch cables, adapters or bundle 3 hdmi to dvi cables.
2 dual-link dvi connectors with one with a double single-link adapter.
True either of these wouldn't allow more than single link resolutions but except for 30" few would notice.
Heck, make the card with an extra pcb and the third connector below the other two, it's been done before.
If you have R&D money to burn, make a model with 3 displayport outputs with 3 displayport to dual-link dvi active adapters bundled.
In the end, there's very little backing to the 'need 2 cards for more than 2 outputs' both ATI and Nvidia have been burning us with so far. Even their own workstation cards prove that, many of which have 3+ outputs from single slot cards.