I am trying to decide which 13" 2012 Macbook Air to get. Here is what I'm wondering: I have been told that if you have 4GB ram, the video card uses 384MB for vram and if you have 8GB ram, the video card uses 512MB for vram. So has anyone compared the two 13" i5 or i7 systems? Did you notice a difference? Gaming, movies etc? I play games like Diablo 3, and will be getting the new sim city in march so I want the best possible performance from the integrated chip. Any insight is greatly appreciated! Thanks.