For the price difference of the R9 290 and the GTX 780, i would say the first build has a better performance per dollar. A r9 290 performs similar to a GTX 780 at a cheaper price.
The power supply you chosen in the first build is a good one. However if you are running a single gpu in the future, then it i overkill, 650W is enough. If you plan to run in crossfire, that power supply is adequate.
Stick to brands such as :Antec, Coolermaster V series, Corsair(AX or HX), EVGA SuperNova G2 series, Seasonic or XFX