Resolution - mix of 960x544 and 1280x720, and some things like fog particles were rendered in half resolution that are rendered in full on PC.
Vsync - Xbox had "smart vsync" i.e. Vsync on if frame rate above 30, and off if below 30. PC doesn't support a mode like this. American Nightmare Xbox360 btw has a selectable Vsync (on, off, smart).
Antialiasing and FXAA - We had 4xAA on Xbox. FXAA was added to American Nightmare.
Anisotropic ******ing - Some textures where it was important had Aniso on Xbox (like the road texture with the yellow line), most were trilinear ******ed only.
Shadow Quality - Xbox360 is somewhere around the medium setting. The rendering differs a bit so no exact comparisons can be made.
SSAO Quality - Xbox360 build had something like the Low setting - maybe with a bit less noise.
Backdrop Quality - Xbox360 Alan Wake used Medium.
GodRay Quality - Xbox360 build had this turned to off except for some specific scenes where we had the performance to turn it on and had most visual impact. The quality was less than "High".
Volumetric Light Quality - Xbox used the "Low" setting.
Draw Distance - Xbox build had this at Full - it was mainly added as an optimization. Draw calls are way more expensive on the PC than they are on the Xbox360, and this reduces draw calls.
LOD Distance - Xbox build had this around the middle mark.
FOV - Middle / default is the one Xbox360 version used too
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