The 580X is just an RX580 that has been clocked a few percent higher. But it gets worse, the RX580 is an identical design to the RX480, with just a few silicon

The 580X is just an RX580 that has been clocked a few percent higher. But it gets worse, the RX580 is an identical design to the RX480, with just a few silicon tweaks to clock slightly higher. Clock for clock, the 580X preforms identically to the RX480 that launched in August 2016.