Well after 5 months of chasing this problem, I may be the happiest user of FS9 on the planet right now.
My problem all along was that somehow I took the Texture folder out of the FS9/Effects folder. I still had all the fx.xxx.bmp files in the effets folder but they were just mixed in with the rest of the xxx.fx files. So consequently my graphics just didn't look right and no one could tell me why.
For example I could not see the tire smoke when an airplane touched down. When I first installed FS9 I remember seeing that effect and being blown away. But for about the last 6 months all I saw were blank/transparent square frames being generated but no smoke. So I knew the effect was being generated but it just wasn't showing up. Now I know why.
The difference is absolutely incredible. I must have accidently gotten rid of the effects/texture folder right around the time I upgraded to a GeForce 5600 graphics card. So all this time now I've never seen what it was capapble of doing. Well now I can't stop grinning. In fact I've had to turn down many of the settings to preserve frame rates. I never had this problem before. FS9 wasn't displaying all the little graphics associated with the various effects so the frame rates stayed pretty high.
But wow what a difference. I never knew what I was missing.
Thank you Hi-D for your help. You made my week.
Here is an example of what this problem looked like before and then after I put in a new texture folder and rounded up all the fx.xxx.bmp files and placed them in that texture folder within the main FS9/effects folder.
Notice the concentric squares of "dust" being generated, but there's no detail to it.

And in the fixed picture, a nice rotorwash with the dust cloud. Much, much better...
