My specs:

Apple iMac 27"

...

what, still no comments? =D

Intel Core i7 860 2.80GHz
8GB DDR3 RAM
ATI Mobility Radeon HD4850

For anybody who runs a 27" iMac like me, well... forget about running the game at full native screen, because it's So Much Resources Overload! You can't keep your 40FPS straight even if you're looking at the ground (wait, maybe for that yes)

So, copying the template from Swordz, I'll give you some good settings:


Resolution: 1920x1080 (try 2560x1440 and prepare to fry eggs on your computer)
General Drawing Quality - 8 (Standard)
Background Drawing Quality - 5 (High)
Shadow Detail - High (because I like it more like that.)

Abient Occlusion - off
Depth of Field - off
Cutscene effects - on (I set it off just for more FPS when I'm on 2560x1440 for screenshots purpose)
hardware mouse - on
Texture Quality - High
Texture Filtering - High

I've tested that when the rain comes, or when you encounter bushes, or when you encounter both and blow your head off, your performance will drop by 30-40%, and I'm still wondering why is that. I've also done things with Catalyst Control Center reducing some Anisotropic Filtering and enabling the Catalyst AI, but still nothing, so I guess it's the limitation of the Mobility Radeon.