@doktor83   I'm pretty sure that you are aware of all these occasions, I mean with the hashdrop.
Cards with 4gb memory dont have this issue, at least to me. They reach maximum hashspeed immediately.
The problem is with the 8gb cards.
Whenever I start your miner one of them, sometimes more, can go up to maximum, others no and they stay low all the time
even after 2,3,4 hours of mining.
Next time I'm starting your miner some other cards or card do the opposite thing. It's a random situation.
To help things out, you of course the developer of a great miner to me, I found out that running GPU-Z at the time your miner runs
and passing throu all cards one by one and then exiting, voula all cards running full speed. Problem solved.
But of course this is not a solution!!!
Maybe something with the interrupts?
I'm  trying to help!