4 gb of ram is enough even in windows 10 and the processor is a good one for mining , many people go for the g 3900 but g4400 makes a difference here as it is more powerful for just about 10-15 dollars more in price.

As for risers get the version 009s or latest because they have all possible connections , 4 pin molex, 6 pin pcie and sata.

You can buy six of them and put 6 graphic cards to your motherboard. Since you are going with 1060 cards a 850 watt modular psu is enough to run them even on full power.