What does lowering graphic settings in Crysis 2 do?

When I lower the graphics I barely see a difference yet I get like 40-60 more fps.What does lowering graphic settings in Crysis 2 do?
Count yourself lucky then!



Small differences will include the amount of "jaggies" which is what anti-aliasing does. Reflections may be turned down a little more, particle effects may be less noticeable, lighting may be a bit more simple,... etc