Trying this out: Natural Graphics Mod | RaceDepartment
I used FRAPS since using photomode supposedly disables SweetFX that the graphics tweak uses. (Not sure if clicking the photomode button emulates F8 or if it just takes the screenshot and doesn't mess with SweetFX...) Will also stop using JPEG screenies with FRAPS since they're way too compressed sometime. Graphics settings were all maxed out, minus AA, which was off, except for FXAA, which was on :). Will start using normal AA.
Now with 4xAA (with FXAA on). FRAPS PNGs (compressed as a JPEG, thanks to imgur...):
With this setup, I average 22FPS, and that's during a 09:00 practice session as Spa with no other cars.
At 800x600 instead of 1920x1080, I get 33FPS... Everything low @ 1920x1080 w/4xAA, I get 180FPS :P.
This is the only game I have where I can't play it maxed out and get acceptable frame rates, and it's still not that visually great (at least compared to pCARS).