Its not bad by any means , 7/10 in my book.
The Good : R9 280X and 8GB of RAM as well as no compatibility issues.
The BAD : You could have dropped the optical drive , Sound card and went for a better CPU , its not really sensible to pay more for the mobo opposed to investing in a better CPU . I know that you got the 990FX for overclocking however you'll never be able to achieve the 8320 levels anyways and you'll still experience some bottlenecks in CPU intensive games due to the high-end GPU and mid range CPU fortunately though not much .
A More sensible choice would have been the 8320 and GA 970 UD3P.
The PSU is very cheap quality and can fail underload moreover its not ideal for overclocking and at that price range a XFX 550W unit would have been a more sensible choice.
Overall : System is Unbalanced a Mixture of bad choices and little knowledge ( no criticism ) , A R9 280 , 8320 and a 550W unit then this would have been a 8.5 in my book however It will act very nice and can be upgraded later .
If not already purchased I'd highly recommend switching processors to a 8320 and Mobo to Gigabyte 970 UD3P moreover XFX 550W or EVGA 600B PSU would be adequate also if budget allows a SSD will work wonders.
If already purchased then Its a solid foundation to build on and a 7 isn't bad at all.
Thanks