First of all, thx for all the answers.
sudo aticonfig --initial --adapter=all -f
then reboot / restart X.
I did that now. Sadly theres no positive effect
First, check if ubuntu recognize your card or not:
If yes, bingo, let's take a look at adapter index. You might be worng when forced the 2nd GPU 3rd index with
aticonfig --adapter=3 --pplib-cmd "set fanspeed 0 85"
If no, reinstalling the driver may fix it
I reinstalled the whole system last night, so it cant be the driver.
Ubuntu recognizes my cards.
miner@BigBang:~$ aticonfig --list-adapter
* 0. 03:00.0 AMD Radeon HD 6990
1. 04:00.0 AMD Radeon HD 6990
2. 07:00.0 AMD Radeon HD 6990
3. 08:00.0 AMD Radeon HD 6990
* - Default adapter
DISPLAY=:0.0 aticonfig --pplib-cmd "set fanspeed 0 80"
DISPLAY=:0.1 aticonfig --pplib-cmd "set fanspeed 0 80"
Did that too. DISPLAY=:0.0 works and sets the fan on the right value.
If i try to control the second adapter with DISPLAY=:0.1, the command is successful, but nothing happens.