External display out problem Fcp Color in lion Mac

I was using Snow Leopard Mac Os 10.6.8 and there was no problem my works in color. I send my computer to technical service because of export problem in Finalcut. They tested the machine and upgrade it to Lion. I'm using Finalcut 7.0.3 and Color 1.5.3. I install the Aja Kona 9.0.5. There is no problem in FinalCut output but i can't see the Color out in external display, there is signal but no video, only black. If i can't solve the problem i will return to Leopard.

How i can solve the problem please help.

My system
Mac OS Lion 10.7.3
2x2.4 Ghz Quad-Core Intel Xenon
10 GB memory
Finalcut 7.0.3 and Color 1.5.3
Aja Kona 9.0.5
Graphic Card: NVIDIA Quadro 4000