Not very well. As a WoW player, I can say that with confidence. Each expansion the graphics requirements go up. Today's IGP from Intel's i* and AMD's APU's would have owned vanilla and probably would have still would have done decent in BC and possibly Wrath. Cata raised the bar a fair amount and MoP even further. I used to run a 7600gt for Vanilla and BC. There is no way it would be playable today. My HD 3870 and PhII just barely get by in 720p it seems when I have to bring that system into use. I used to run Ultra with my rig back in Cata. I now run on good to high on everything. Only SSAO is disabled and shadows I keep on low to get similar FPS. I often keep ground clutter and water effects on the lower end as well, but that is more so it is easier for me to see certain items in MoP that can be difficult to see with a bunch of grass in the way or the water reflecting a lot. In many MoP areas, I still dip to lower FPS than I saw most of Cata. I even play on a very low populated server. If I were on say, Illidan, I would probably have to go even lower on settings.