Are you planning on adding a video card? or are you using the integrated graphics only? The power supply will work just fine, but I don't think you need that many watts. It may be possible to get something smaller and put the money elsewhere in your build.
I remember seeing a radeon 6670 for $50 at ncix. If you've got the budget, that would make it so your build can actually max out some good newer games at 1080p smoothly (excluding AA) and it's the highest gpu the A10 can crossfire with.