Just to share my experience with Blockchain drivers, electricity, etc.

Pre-Previous state  :

8x Sapphire RX580 Nitro+ Special Edition (blue one) - Samsung mem - flashed silent bios (1750 strip -> 2000 strip) - nothing special
17.7.1 - drivers
-cclock 1150;-mclock 2200;-cvddc 840;-mvddc 840;
power drain - ~1170W measured on wall (idle system 150W)
running ROCK stable more than two weeks
~212 MHs

Previous state :

8x Sapphire RX580 Nitro+ Special Edition (blue one) - Samsung mem - flashed silent bios (1750 strip -> 2000 strip) - nothing special
Aug23 blockchain drivers
-cclock 1150;-mclock 2200;-cvddc 875;-mvddc 875;
power drain - ~1270+/-20W measured on wall (idle system 150W)
miner sometimes restart + lot of GPU memory errors
~237MHs


Current state :

8x Sapphire RX580 Nitro+ Special Edition (blue one) - Samsung mem + Uber-mix v 3.1 straps flashed silent bios
Aug23 blockchain drivers 
-cclock 1150;-mclock 2125;-cvddc 880;-mvddc 880;
power drain - ~1380W+/-20W measured on wall (idle system 150W)
miner without restarts - minimum GPU memory errors
~ 245MHs

Still digging around to lower electricity drainage..