Serious problem

I am still getting “Serious Problem has occured” message when I record using 3rd party plugins. I have all the latest 64 bit drivers and disabled multi-threading in the bios. On the latest crash it mensioned “Video decoder crash, will save under a different name as program is in an unstable state” Also when viewing the pdf help files in C6, scanning or draging the image left to right, the screen flickers and freezes. If I close and re-open the help menue, its ok again untill I do the same again. Could thisproblem be the graphics card and be connected to the serious problem I keep getting.