This is still a theory, but after installing some addon sceneries with birds at Vancouver I noticed a substantial reduction in my framerate and increased microstutters. As soon as I disabled the scenery the problem was gone. I then tested my framerates around Orcas Island with a scenery with birds and other marine life installed. While performance in this area is still acceptable with the birds, etc. enabled as it is a rural area my frame rates were 30 to 50 percent lower than without the bird scenery. Even when I was flying towards the scenery area from about 10 miles away from where the birds show up my frame rates were cut in half when the bird scenery was enabled suggesting that this scenery affects framerates far from where it is even visible. Unfortunately we don't have any setting in the GUI to turn bird animations off, so I'm wondering if anyone might know which files control these around major cities and find a way to disable them. It would also be good if others could test this to verify my findings.ASUS A8X-SATHLON64-4000 oc to 2.6 GHZ2048mb PC3200RAM6600GT 128mb GRAPHICS CARDWD 120GB IDE DRIVERegards Martin

"Unfortunately we don't have any setting in the GUI to turn bird animations off"Advanced Animations in FSX graphic settings control panel. (its a check box)You'll lose the wingflex as well if you turn it off.I wouldn't rename the corresonding "city".bgl to xxx etc in the scenery folder, as you will lose the airport terminal and all custom buildings for its area, maybe scale back the scenery complexity slider a notch instead.Not for certain, but I believe the birds are associated to the ships in most cases as well, (based on me adding ships with object placer and seeing birds after thier placement - like fishing trawler and cruiseship, or maybe it was the warf - haven't verified which) you might want to scroll back your ship traffic as well if you have it cranked up.If the upcoming "Service Pack 1" does what its intended, we should have a little more head room perfromance wise. Here's Hoping ..Regards'Garett

I actually keep all land and air traffic turned off my self, and that seems to save many CPU cycles. Depending on how you use the flight sim this may not be feasable, but for me, since I just like to fly around enjoying the sim, and do not interact with airports and traffic, this makes sense as I can then enjoy a bit nicer scenery.

Any animation, whether it be jetways or birds, will hurt framerate quite a bit. Go to any airport, and when all 45 jetways are first moving, you'll get terrible frame rate. Once the jetways stop, fps will double at least.But the PRIMARY problem in the large cities is the file named "default.xml". What I do not know, is if this problem is the result of a memory leak (as it was with FS9's xml file, especially pre-patch), or if it is a result of the sheer amount of xml code being parsed (5+ megs at least).RhettAMD 3700+ (@2310 mhz), eVGA 7800GT 256 (Guru3D 93.71), ASUS A8N-E, PC Power 510 SLI, 2 GB Corsair XMS 2.5-3-3-8 (1T), WD 250 gig 7200 rpm SATA2, CoolerMaster Praetorian case

you can simply delete the Animals folder or disable it in the fsx.cfg. (//)