JJ1217 :
Replace the 7870 GHZ with a 7870 LE/XT, and get a better power supply. Preferably something from XFX, Corsair, Seasonic and Antec.
He's got a 7950 in that build, not a 7970.
OP, you don't need a PSU with that much power. 650W is fine if you plan on staying single GPU, if you ever think you'll Crossfire that 7950, then go for 750W. +1 for the above brands...Corsair in particular have a very good RMA service, should you be in need of it.
You should save some money by getting a smaller PSU, so get an SSD boot drive. For usage, that it probably one of the more important components.
Make sure you get 2x4GB RAM and not 1x8GB. RAM is designed to work in pairs for you to get the maximum speed.
I don't see an aftermarket cooler on that build, and you have a 'K' CPU so I presume you'll overclock...make sure to get proper cooling. Something like a Hyper-212 would be fine.