If you are stuck with a DirectX 9 GPU or you are too lazy to install Windows Vista, then here is a nice tweak for you. Apparently, you can enable some cool Crysis DirectX 10 features without having a DirectX 10 GPU, DirectX 10 or Windows Vista, all you have to do is to edit the configuration files inside Game\Config\CVarGroups. You have to modify all files and replace the Very High variables , with the high  variables. If you find it too hard, then I have done it for you, just download this file
and extract it the CVarGroups directory and pick ‘High’ settings inside the game. Credit goes to LennyRhys
for the great discovery.