Get the right adapters and you can or using two DVI's and a HDMI, However depending on what your running its going to slow everything down. For example, if playing a game on all three monitors your graphics card would die, however using maybe 2D less labour intensive applications could work with a game on another screen. If your just using normal applications on these monitors though then it will be fine.
Oh man, this thread is old. But I've acquired the GX 780 a while back. And everything is working fine.
I don't need any adapter, windows instantly identified the three displays. I am however, only using one display for gaming.