The CPU should be fine in most games but only just if you go higher than a RX 470/1060 3GB. That said, i would recommend an RX 480 4GB over both since they usually hover around the 1060 3GB price range and mostly outperforms that and the RX 470 of course. How much are the 2 you are looking at? Here is the cheapest RX 480 on PCP > https://pcpartpicker.com/product/WfyxFT/asus-radeon-rx-480-4gb-dual-video-card-dual-rx480-o4g. $188 USD.
If you have to get one of those cards it would probably be the 1060 3GB. I'm not very keen on recommending a 3GB card especially at that price bracket due to my VRAM experiences in modern games (at 1080p as well) but it is stronger than the RX 470 in most games. Hope this helps