I have been messing with this a bunch over the last few days. I put an ATI card in and encountered the same problem. The only thing that seems to have made a difference is Anti Aliasing. It happens every time when AA is selected but not when its not. Of course I thought I had it figured out last time so who knows.

Hi guys,We should consolidate this into one topic. There are currently 2 matching topics for this one:http://forums1.avsim.net/index.php?showtopic=125198andhttp://forums1.avsim.net/index.php?showtopic=240029&st=0So far, the fixes seem to be:Revert to XP 64 instead of VistaOR run in DirectX 10 mode in Vista.-stefan