Ambient Occlusion for Geforce cards: http://www.dsogaming.com/news/the-elder-scrolls-v-skyrim-how-to-enable-ambient-occlusion/
Perhaps I'm blind, but.... in that article, there's example pics for with & without AO. What difference am I supposed to be seeing between them? It isn't obvious. (a bit more contrast in the shadows, maybe?

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