I bought an AMD 7870 graphics card for my pc. The HIS 7870 GHz edition with 2gb of RAM to be exact. This care has one DVI port, one HDMI, and two mini display ports. I bought a mini display port (mDP) to DVI adapter and I have both an hdmi One and VGA coming in the mail tomorrow too. When I plug in a DVI cord, an HDMI cord, and the DVI to mDP adaptor, only two of the three monitors work. Why does this happen? The box says it supports 6 displays, I'm using half that and it won't work. I could easily use 3 displays on my old GT 640. Help!!!