I have to agree with "esrever"
- the roughly $50 saved by getting 8GB vs 16GB should be put towards a better CPU
- the FX-4100 isn't a great gaming CPU. It's "okay" but not when paired with a $250 graphics card.
*I don't mind making build recommends but I'd have to know the overall hardware budget.
However, building a gaming system is all about BALANCING the parts for the best gaming performance for the price. Simply put, 16GB + FX-4100 + $250 graphics card is out of balance.