Alexdiaz :
Which one should I get? I won't get a dGPU until around Christmas so I would have to use the iGPU for a while. I'm not going to play any demanding games. Only casual tiles such as Minecraft, TF2, Gmod, and Rust.
I would say go with the pentium so you're on a haswell board. if you ever decide to upgrade, you've got way more options, while AMD's FM2+ is kinda a shitshow, as far as enthusiast performance (this is the main reason i am also generally against the X4 750k.)
While AMD's APU's are faster graphics-wise than intel's HD graphics, the 8470d on the A6 6400k isnt a large step up from the HD 4000. If you can step up to the $99 pricepoint, the A8-6600k might not be a terrible choice. On the other hand, the Pentium G3258 is actually a very strong low end processor with intel HD 4000 graphics at $75.
So, since you're going to get dedicated graphics, get a Pentium G3258. Its a fairly fast little chip that runs games pretty well, and when you get dedicated graphics it's gonna be a great little workhorse. Also, if you decide to upgrade later, you've either got the option of overclocking the pentium to get i3 level performance for free, or to upgrade on the haswell socket, which, lets be honest, is the best choice for processors right now.
tl;dr: buy a pentium g3258 for your budget box.