Hi,
Using an adapter will not Work.
Displayport 1.2 has enough bandwidth for 4 FullHD streams and is Multistream compatible, so you can send different video streams trough one cable.
Thats how the MST Hub works, it splits the incoming streams to each monitor.
Now if you use a HDMI or DVI output on your card you cannot get multiple streams trough one cable, therefore the MST Hub will not work.
It MIGHT work if you card could send a DP signal over the HDMI port out, but i don't think the GTX570 can do this.
doesn't look good