AMD is looking to keep the ball rolling with new GPU releases until the new Vega architecture arrives later this year. One of the methods AMD is doing this by is refreshing its existing GPU range to stay competitive, both the RX 470 and RX 480 are being refreshed to produce the RX 570 and RX 580.
Any major computer upgrade generally requires a full software reinstall too. No so if you heed the advice in the guide to Upgrading a Motherboard without Reinstalling. PCSTATS Tips