Probably the 7970 is the closest to the 760, though a tad behind in performance benchmarks (depending on the cards exact specs, I suppose). I'm an nVidia guy, so of course I'm going to say I like nVidia better if it's just a preference issue. However, AMD cards tend to have excellent performance/price in the under $200 sector especially; and of course also have excellent high end offerings as well. I'd go with the 760, a little less pricey than it's counter part after a quick glance.
AMD CPU system doesn't necessarily make a difference, unless you like consistency in your components
Cheers!