[{HVY-E}Jinxx]

The one BIGGEST factor is the higher resolution objects and cockpits. Stock are 128 x 128 and 512 x 512. Most of the high res stuff the guys have been putting out are 1024 x 1024.

Also, the larger maps and denser population areas are a factor as well.

Even with my machine, if I run everything at max and fly over a densely populated area, I drop from 204fps to about 22fps.