Hi Marcus! If you pursue with purchasing the parts outlined in your link, you shouldn't have to buy any aftermarket wires. The EVGA Supernova 650 G2 has the eight pin and six pin PCIE cables you will need to power the graphics card. It also comes equipped with two SATA cables; which is enough to power two hard drives or SSDs. Additionally, the aformentioned Samgsung EVO comes with the data cable you need for it to function.
As for the overall price, there are two components that I would reconsider purchasing. Assuming this computer is for gaming or editing, the Corsair Dominator Platinum 16GB 2X8GB DDR4-3000 would show negligible performance differences, and is likely to be ample RAM for almost any task. If the PC is for gaming, the...