You might consider a different motherboard, since that one probably will need a BIOS flash before it can work with the 8320 cpu. Unless you have an older amd cpu, you wont be able to boot the motherboard to flash it (AMD 760G, 880G and 990FX/990x work with vishera cpu's out of the box).
You don't mention what brand psu you are getting, but a 750 watt would be more than enough, even a good 550 watt would be enough if not overclocking.
For the ram you probably already know you should get 2 stick of 4 gb instead of 1 stick of 8. It will enable dual channel for 1-2% performance increase. Not much but it costs about the same so why not.