So basically i am going to build my first pc and i am aiming for a editing pc. i will be using applications like Sony Vegas, Adobe premiere, cinema 4d and most importantly adobe after effects cs6. now for the gpu i am considering going with a [Sapphire Nitro Radeon RX460 4G] i will be doing 1080 editing at 60fps max and will be doing a small amount of 3d work. so what i am asking is if the [Sapphire Nitro Radeon RX460 4G] is adequate for after effects cs6 and if there are any other good graphics cards for ae cs6 that are in the $100-$200 price range
Irrelevant. AE isn't great on GPU acceleration, even more so in a legacy version like CS6. The Raytrace 3D stuff doesn't work with AMD cards to boot, it's deprecated and as a C4D user you'd probably not use it much, if at all, anyway. Therefore any decision what card to buy must be based on your other programs or specific plug-ins that may require GPU features.