Fatal Error in DirectX Diagnotic tool

In the last couple days I have gotten this error a couple times. It does not happen every time I start FS. It has only happened since I installed ASX and XG but I have no indication that that is the problem.Within 5 seconds of hitting the FSX icon, I get the flash screen and a error message stating:"DirectX diagnostic tool had encounter a problem and needs to close."When you click ok, don't send it tells you that is a fatal error and FSX shuts down.I went in to DXdiag and it mentioned that I had a direct 3d error recently and it asked me if I wanted to skip that step, I said no. When I did the direct 3d test the cube was spinning much faster than I recall - so fast it was a blur.Any ideas?