I have two Sapphire RX580 Nitro+ Special Edition (Blue Shroud/LEDs)

ROM Located at link below:
https://drive.google.com/open?id=0B3Sz3h7CSB_4TG1lWXF3dGtDdkU


Here's what I did:

Copy the following strap to 2:1750, 2:2000, 2:2250 only.
777000000000000022AA1C00B56A6D46C0551017BE8E060C006AE6000C081420EA8900AB0300000 01B162C31C0313F17

Change third line of "Memory" section to "2000." The purpose is that we're applying more aggressive timings, so I'm downclocking the memory to compensate (just in case). This way I have less of a chance of uploading unstable settings and giving myself a good headache trying to fix it. You can overclock later in Afterburner.

This got me to 28Mh/s stock.

In afterburner I then tested each card slowly and systematically. Each card is different and can handle different settings. Surprisingly, I found the below settings worked for both of my cards (81.1% and 76.7% ASICs)

-96mv
-21% Power Limit
- 1154Mhz Core
- 2250Mhz Memory

Yields 29.2 MH/s Eth + 497Mh/s SIA in dual-mining mode.
Yields 30.6 MH/s Eth only (test DAG 130)
Power Usage = 132W (81.1% ASIC)
Power Usage = 137W (76.7% ASIC)

Of the 12 cards I own, these are the only two cards that can hit 2250Mhz on the memory and run stable while dual mining. After 90 minutes, I have 3 errors on 1 card, and 6 errors on the other according to HWInfo64, which is very acceptable.

Obviously much better power usage to performance on the Nitro+ RX570 cards, but these are the best RX580s I've worked with hands down.

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