I’m on 19mhs currently on asus p5e deluxe. A week ago it was around 24 on same machine with rx580 4gb gigabyte Something wrong that I’m sure. But I don’t know what’s wrong.
Are you in Gen3x16?
Gen2 x16
There is your problem, not enough speed on the PCIE gen 2 port, it's only the same as gen 3 8x... Which isn't good enough for Zombie I guess.