hi benjamin,
i used in the past the 7870, this card was o.k. i deactivated the second graphics core because this config was not working with dataton 4.x and 5.x.
with the availability of atis V8800 i changed all may machines (12 pcs.) to this adapter.
4 outputs and connectivity to the s400 synch boards. more speed (just a feeling), less cpu usage.
i´ve tested also two W7000, runs also smooth with 3d content on all 4 outputs. but i´m happier with the V8800 and W8000.
my systems running also as touring systems and i never had problems with the graphic cards.
you can´t synch the 7970,as i know.
are you happy with the dp hubs?
i never tryed it.
cheers sven