Being that I am restricted to $450 (at the moment) for everything minus the PSU (and to OfficeDepot for the PSU at only $70 max) this is what i found to be capable of playing some games circa late 2011 and lower at reasonable settings though I am skeptical of my research.
Would the PSU be sufficient? Are there any issues with this build/suggestions?
You would be fine with that psu, probably overkill. The 6670 is the best priced card out there, so you are good with that. You could probably get a lot of those parts for cheaper on newegg. Also, the 6670 you have listed is an awful buy. The card won't utilize the 2gb ram so you don't need it, and it has ddr3, so it will be slow as hell. Get a different 6670.
This 6670 is far better http://www.newegg.com/Product/Product.aspx?Item=N82E168...