hello-on the ASRock web sight under the AMD 990FX mother boards and the fataility one board it says you can run a 3 way HD6670 graphics cards on this board and AMDs chart says you can also using an external crossfireX bridge-but for the life of me i cant find an external crossfireX bridge? are we just talking a short DVI to DVI cord or a short DVI to HDMI?