-"But what is also odd is that users who have replaced the autogen textures with low-resolution replacement textures should not experience the same loss of performance, but that's clearly not the case.-"You should take a look in your FSim SceneryGenerictexture folder, there are additional autogen textures that may have an affect. They range in resolution up to 1024x1024.Kurt M

No, the mesh isn't the problem.Some areas like Miami work well. Not great at 16-20 FPS but that's normal because of the complexity of the scenery.Tampa, which is also pretty flat, however, turns the sim into a slideshow. Tampa and Miami have a fairly similar landclass, they're both flat areas, yet the framerate over Miami Intl. is twice that of the framerate over Tampa.I have found that Hawaii works without slowdowns, even with an addon mesh, and it's a very computing intensive area.The slowdowns are pretty randomly scattered, but they always happen at the same places.This isn't about scenery being too complex for the computer, or people running excessively high detail settings. There's nothing special about the scenery at e.g. Portland to warrant this extreme loss of performance (below 10 FPS). This is almost certainly the result a bug or conflict causing severe loss of performance. That's why I'm trying to find out if it happens on all systems or only on systems with a certain configuration. From a thread at Flightsim.com, it appears that it happens to 9x as well as 2k/xp. It also seems to happen on both AMD and Intel systems. I haven't found out yet if it happens with both Geforce and Radeon cards. I would appreciate some results from users of Geforce cards (GF4 and GF-FX).(mesh at 100%)http://forums.avsim.net/user_files/32810.jpghttp://forums.avsim.net/user_files/32812.jpghttp://forums.avsim.net/user_files/32813.jpg

Hi JimmiG.Could you post some saved example flights as a zipped file attachment?That would allow viewers of these posts to try them on their systems. with different settings.The "My Flights" are stored in a folder similar to this:C:Documents and SettingsDick.LUDOWRMy DocumentsFlight Simulator FilesIf you have My Documents on the desktop, it they will be in the "Flight Simulator Files" folder. Just include the *.flt and *.wx of some problem flights and a couple of non-problem flights, and a text file of your settings and results and expectations. That way we'll all be seeing something that's similar, and we'll see if this is a system/hardware issue or a fault of the sim.Dick

That's a good idea. I'll do that tomorrow.