The latest AMD Adreniline drivers are the ones you want to use with Windows v1709. The compute toggle is is under AMD settings. You need to set it under each card and reboot for it to take effect.
The lastest Polaris Bios Editor v1.6.6 'one click timing patch' worked very well for the latest Sapphire RX 580 Nitro+ RX 580 8GB card that came with Micron memory. It's been running very stable.
Thanks Vann. I tried on time click patch and a few other mods posted on this forum and elsewhere and no matter what I can't get more than 24.5 Mh/s. Am dual mining ETH + SIA using Claymore 10.2 Do you think that might be an issue? What are the flags I need to set in Claymore?
I have uploaded my Stock ROM here. Anychance you can take a look. No worries if you can't. Thanks,