As any true miner knows the RX580 has released. The cards are not much different than the RX480 from a mining standpoint, not much at all in fact. They incorporate a new bios with timings that have new values and also have higher default clocks on both the core and the memory. The cards share the same Russian Roulette when it comes to memory manufacturer (Hynix, Elpida, Samsung, Micron) and you never know which one your card may have because supply and demand determine what the manufacturer uses that week. If you get a micron return that piece of shit ASAP. I have had great luck with Hynix cards and Elpida cards thus far but they are the only cards I have received. Here is proof that backs up my statement of the RX580 being just a RX480 with a new Bios and clock speeds, https://www.youtube.com/watch?v=eaE_6eFaYjs
Someone confirmed this by putting BIOS from a RX580 onto a RX480 and were successful.
Here is the lovely RX580 BIOS, use at your own risk. I am not sure if it is for Hynix Elpida Samsung or Micron. https://www.techpowerup.com/vgabios/191262/sapphire-rx580-8192-170320
I hope i did not violate any forum rules here. I am new to this site. Happy Mining/Trading!