I have lowered from 2186 to 2132 on my 580 8gb  micron rigs almost while moving to 832 the voltage.
Non perfect but it works stable with version 1.2.3 if I remember correctly

On the test rigs with 3 elpida 570 pulse 4gb  I simply reinstalled my original bios WITHOUT the new straps and set the same value I had before (subtrack 24) and I'm getting 1970 mh/s with neoscrypt, so not bad.
I need to restart the rig once a day as Cpu utilization tend to increase.
 

Neoscrypt only for both rigs.

You wrote that also criptonight can be a good choice for AMD, but I haven't find a good coin to mine that generate the same profit as ETH.

If you can, please  hint me on that.Tx