At last I have found a solid solution for my Nvidia-based PC. I am running the Win 7 RC 64-bit but it should be the same for Vista 64-bit.1. Update display drivers to 185.85.2. In the Nvidia control panel, Global settings, use the following settings:a. Anisotropic filtering: "Application controlled." b. Antialiasing mode: "Application controlled."c. Multi-display/mixed-GPU acceleration: "Compatibility performance mode."3. On the Properties page of your FSX.EXE executable, go to the Compatibility tab and select "Run this program in compatibility mode for: Windows XP (Service Pack 2)."4. Load FSX. In the Display options, choose Anisotropic filtering and put a tick in the Antialiasing box. 5. See what happens.The critical steps seem to be the combination of 2c. and 3.The downside is that you can only use the "built in" FSX anisotropic filtering and antialiasing (or at least that is all I can use). But that is a small price to pay, IMHO. My apologies in advance if this is another false dawn: but on my PC, it's now worked often enough for me to be really confident that I've got it licked. And even it turns out still to be broken, the IMPROVEMENT in stability by fiddling with these settings (coupled with the fact that FSX does not have these problems in DX10 mode) demonstrates - to me - that we are looking at something to do with running a DX9 application under a DX10-based desktop with current Nvidia graphics drivers.Tim

Will give it a go Tim and advise, thanx.

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