if it was me i'd go with the I3 7850 combo. it tends to out perform all of amd's line up, unless there overclocked enough, plus most of the time it's better to spend a little extra on gpu power then cpu. unless your playing more cpu bound games like RTS's or simulations such as FSX.
so why only these two combos
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even though threading is not as good as an actual core we ain't talking about a dual core E8500 vs Q6600 here.