Good thing you opened a thread about this problem so we can solve it.
Already had 2 frames ready for 12x570, i now made one more so i can run 4 cards per frame heh.
I will try to help in resolving this issue, we realy don't want 4gpu rigs when we can have 6 or more

Did you try flashing them to 470 bioses?
No, i'm trying it this evening and i'll write how does it work, but guys, you better think un other way to solve the issue becouse maybe it doesnt work, whatever you think that mayor work, tell me