Im going to go back to the point of this thread. If im wrong about anything, im sorry. I try to be correct, but im not perfect.
If the build is being based off it's ability to still run games well 2-3 years from now(Title says 2-3 years), an FX 6300 will be a better choice currently. Of course, in a year, there will be new CPU options, so anything i say here will probably be invalid.
Look at the progress made in the last 2-3 years to make software use 4 threads and Hyper Threading properly. With Intel releasing 8 core Extreme edition at the end of the year, and the '5820K' supposedly being 6C/12T for $400, 6+ threads will begin to get more optimised, instead of 2 - 4 threads, like we have currently.
Neither AM3+ or LGA 1150 have a long term upgrade path, 1150 is dead after Broadwell.
Its a hard time to buy a CPU now, because AM3+ is dead, with no upgrades, and LGA 1150 will be dead by the end of next year at the most.
Anyone building in the next 6-12 months is essentially stuck with knowing that if they want to upgrade their CPU to a new series in 12-18 months, they will need a new board too. Of course, this happens with every Intel socket cycle, but it still makes it hard to make a decision on a build.
Feel free to correct everything i said, but its my opinion at this point.
As far as resolution and CPU, your CPU can bottleneck the GPU, meaning that the GPU isnt getting information fast enough to process and display the image correctly.
Playing in 4K (4x 1080p), for example, you would probably want a high end i5 or i7, because the amount of bandwidth required for a high end GPU to display at that resolution is insane.Of course, a GPU to run that resolution smoothly costs a bit.