Here is some stuff you need to know:
1: AMD mobos only support PCI-e 2.0. This means, in the future of gaming, when games start taking advantage of PCI-e 3.0, your mobo will start bottlenecking the card. This means, that your card won't be able to use all of its resources, and therefor, decrease performance. In the Intel builds, their mobos PCI-e 3.0 support will help them to use their GPU to its full potential.
2: Your not getting a six-core CPU, your getting a three real cores. Each of those real cores (that contains two AMD cores) only account for 1.54 cores, where two real cores would account for 1.9-2.0 cores (Intel's Hyper-threading is equal to 1.23 cores.)
Source 1
Source 2 (scroll down to the list of FX CPUs, and look at their core number. Should be something like 3 (6).)
Source 3 (Most important to understand)
3: AMD CPUs use a lot more watts. So, eventually that energy bill will catch up to the extra money for the Intel CPU.
4: AMDs FX series, is old, and dead. Down the road, you have room to upgrade with Intel. With AMD, about your best CPU is going to be a eight "core" CPU, that is about equal to a i5 (
here). Where, with Intel, you could upgrade to an i7.
I would get the i3.