Is anyone here mining with Windows and R9 Nano (or maybe Fury)?

Under Linux, Silent Army developers talk from "44 - 45 Sol with R9 Nano possible".
If I start one mining task, every Nano delivers 22-23 Sol - half of the desired hasrate above, fine.
But if I start a second task, the Nanos drop down to 2x 15-16 Sol - far away from 44-45 Sol.

Any experiences or ideas?