edited:I just picked up a few new cards,
Sapphire Nitro RX570-8GB The box actually contained a Sapphire Pulse RX580-4GB(Elpida).

-- Stock: 565 H/s XMR
MSI RX580-4GB(Elpida) -- Stock: 640 H/s XMR
MSI Armor RX570-4GB(Elpida) -- Stock: 580 H/s XMR
I'll post some modded bios' and hash rates in a few hours...
@mrnoname I'll make a nitro 4gb bios while I'm at it.
edit:

Maybe some day I'll find a 570/580 card with 2250 ram... but today is not the day. I've noticed the mfg. only put 2000 ram in all the 4gb cards, they save it all for the 8gb cards it seems??