i like nvidia over ati, but yeah the 7850 its a nice one too, i would still save a little more to get the 660 gtx :P, but thats me
Well there is always the differences like Nvidia has better software like physX, v-sync, & fxaa but they aren't supported by many games. Nvidia also tends to run cooler, quieter, & use less power. Amd has better 5760x1080 support(nvidia for 3d), overclocking monsters, & better from a raw performance stand point. Really it comes down too price & what games you play if you read a benchmark or two you get an idea which cards work better for what games. Amd makes better budget cards while nvidia has better higher end cards.