Your parts selection is very sound. The CPU is perfect for gaming, best performance/price in fact.
A SSD as your OS and applications will make the biggest difference you have ever seen and I can not recommend it enough.
VGA well that is such a personal choice that I tend to stay out of any discussion about them. Just going to add that both AMD and nVid high end cards are very good and quite equal at the minute. It comes down to personal preference to how stuff looks. Your 560 will be good for some time still, and with a new VGA model (both red and green) some time in the near future it would be prudent to hold off buying now.
Your cooling solution is good so nothing needs be said there.
Ram on the Z77 is pretty much any 16GB kit that you can get at a good price. Most of the vendors use the same chips and the ram all performs the same in real world. Size is now more important than speed in real world, with 16GB being the current sweet spot.
And lastly enjoy.
🙂
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