First of all Mary Christmas ! to everyone here
Second put the cpu at least on 400Mhz fsb, third crossfire or sli doesn't work without the bridge between the video cards.
Check how is mounted the mainboard, maybe you missed a mounting screw on the case.
Try with only one card and see what is the performance without, and with overclock at 400MHz. That mainboard supports 400Mhz without any problems (QX9770 works on 1600 FSB (400Mhz)).