Starting to think all these posts about 4gb 570 ELPIDA cards hashing over 28 are fake.
Possibly thats a Gigabyte RX 580 8gb card doing the 30s and he didn't read the topic.
I got both 570 gigabyte models coming in about a week (Aorus and Gaming)... Will post the results here.
Bought one of these Gigabyte RX570 4GB Gaming cards to try it out and so far utterly disappointed.
Win 10 wouldn't recognize it along with my Sapphire RX470's rear blowers (love those) no matter what, so I unplugged all the Sapphire's, plugged this is and restarted in safe mode, used DDU to uninstall the driver, restarted, then installed the latest AMD Driver, upon which it got recognized. When I removed it and plugged in the Sapphires, windows wouldn't recognize then, so had to boot into safe mode, DDU and start again and let windows automaticaly recognize and install the driver.
It has Elpida memory, so I did the same bios updates as on the Sapphire's, i.e. copy 1500 timings to the higher numbers.
Underclocking the GPU to 1100 and overclocking Memory to 2000 like I do with the Sapphires, resulted in total instability and still only 25 mh/s - the Sapphires all yield 28.2 - 28.5 mh/s
I added this to my ethos (after updating to 1.2.1) rig and it was recognized. It will start out hashing at 28 mh/s for a minute, then drop down to 24.5 - 26.5 but with a very high incorrect / rejection rate.
Just changed the amdgpu settings with memory clock at 1920 and now it seems to be hashing at 27.175 constantly. So its at least 1mh/s slower than the Sapphire's and seems to be drawing much more power. Definitely not going to build a new rig with all of these.