regards; someone has a valid configuration for 7970 or rx280 the most I get is 400 h / s
sounds about right for the older cards...
do you mean R9-280?
I run a RX560 and see at most 380h/s but typically ~320.
check
https://www.xmrstak.com/ It is the place people post their configs.
You may need to mess with the AMD.txt file and fine tune your particular cards.