I’m not sure why AMD release the RX 500X Series … there’s no difference between the original RX 500 series!
AMD today has officially released specs and the listing of graphics cards that are being rebranded to the OEM-only RX 500X series. For all the rumors and speculation that abounded around a super-charged, maybe even Vega-sprinkled new Polaris architecture from AMD has seen their dreams of interesting times squelched unceremoniously.
What were before expected reports have now been rendered true: these are nothing more than an OEM-specific rebrand of AMD’s RX 500 graphics cards. They’re just direct rebadges – not a single MHz was increased across the entire portfolio, except for one lonely graphics card: the RX 550X has apparently seen a bump in clock speeds, from the RX 550’s “up to 1183 MHz” to the RX 550X’s “up to 1287 MHz). Aside from that, folks, move along: there’s nothing to see here.
Source: AMD’s RX 500 X Series Official Page