Thank you @tytran I'd be happy to help and see if we can get your rig running back at max Mh/s. I'd just need to know a couple things about your rig and I'll share what I know or at least point you in the right direction. I'm a Windows 10 miner so as long as we are on the same platform I should be able to help.
What GPUs, drivers, miner and ROM (stock or modded) are you running?
Also, have you tried uninstalling the drivers using DDU and reinstalling with all of the cards connected?