...for you guys who have a DX10 card and are still reluctant to run in DX10 Preview mode: http://davenunez.wordpress.com/2009/02/01/getting-the-most-of-fsx-in-dx10-mode/

My own tests show frame rates 100-200% higher in DX10 preview mode vs. DX9. Why settle for lower frame rates and poorer graphics? Use DX10 preview mode and push those sliders to the right.

I use DX9 mostly since half my aircraft go screwy in DX10

Some of my add-on terrain has missing textures in dx10. That's why I run DX9. I like the self shadowing cockpits in dx10 though.

Dave, Tim, both your reasons are understandable. But how do you tolerate the slower framerates or turning down the graphics to get higher frames? That's my problem. Where I have my sliders, if I'm getting 22 FPS in the middle of Manhattan at low altitude (just above and just below the rooftops of skyscrapers) with DX10 preview checked, I get 5-9 frames per second in DX9. Obviously, that's not acceptable, so I wind up having to push my sliders to the left, only to no longer see certain buildings and stuff because the terrain is less dense. It's the framerate versus graphics tradeoff that bothers me more than anything else. I don't want to have to tradeoff as much as DX9 forces you. Second would be add-on planes. Only a few companies produce add-on aircraft that are DX10 compatible. I really have to shop around.

Have you gone to this website?

http://www.venetubo.com/fsx.html

My take on the DX10 preview is this: it gives you better looking water and nice virtual cockpit shadowing, that's about it!

The downside? It forces you to use the FSX in-game Anisotropic filtering and Anti-aliasing, which has been documented as being a 2xAA by the way, completly bypassing your graphic card AA/AF settings.

As far as I'm concerned, I'm getting far better graphics using DX9 mode and ATI Catalyst Super Sample 8xFSAA and 16xFSAF.

I'm not seeing the nice dx10 VC shadowing and the water looks a little less shiny, but that's the sort of things I easily do not notice anymore once in flight.

I'm locked at 35fps using the external FPS Limiter and never go lower than that on my hardware (Phenom II X4@3.8ghz/Asus 6850HD 900/1100) with almost everything completly maxed out. Everything is silky smooth and looks marvelous!

My 0.02