Framelock when two graphics cards in the same box
I have two machines that can hold two graphics cards (Quadra FX4500) in each box. I would like to connect four displays on the 4 gfx cards in the two boxes. So my questions are:
(1) How many nVidia G-sync cards do I need for each box: one ot two?
(2) Any documents available for configing this kind of setup on Linux.
Thanks in advance.