PSU for HD 7970 and FX 8320

The Wattage is enough, but Cooler Master Elite is too low in quality to be worth using.
If you have low budget, COrsair CX500 would be better choice. But you can also find some 550W XFX at around same price which would be even better.
 
HD 7970 need 6-pin & 8-pin PCIe power connectors and Corsair 520HX only has two 6-pin connectors. You would have to get an adapter or a power supply that has better amperage with proper connectors.