Yeah, nice to have a wealth tuft sticking out your wallet, but better to step down to something like a GTX660 if you could get a similar deal. The GTX480 will perform nicely 1080p, AA and max in most games, but that's not the problem... 250 watts TDP (and that was an optimistic TDP too - it will easily exceed it), and excessive fan noise were the problems.
That power consumption will eat into the money you save (it's well above what your GTX680 would consume). If you don't mind that and the noise though, go for it. Closest current-gen GPU would be the 7850, so you could look at benchmarks to see how that performs. Worst case scenario:http://www.tomshardware.co.uk/far-cry-3-performance-benchmark,review-32584-6.html
Any other game you should be fine with.