1- i've first uninstalled samsung-scripts, then installed samsung-tools. Now i can't change the britghtness with Fn key.
Both 'samsung-scripts' and 'samsung-tools' don't manage the FN keys for brightness control, since they usually work out-of-the-box. So the problem is not related with them in any way.
Anyway, try to install 'samsung-backlight', reboot and check if the keys work.
2- i can't change the fan speed : "samsung-tools --cpu silent" says that the fan control is not available
'samsung-tools' depends on the 'easy-slow-down-manager' kernel module to properly work, which is installed as dependency as soon you install 'samsung-tools'.
After the installation, you have to reboot to have everything in place and working.
3- i can't access to the Preferences of the gnome applet of samsung-tools : if i click on this menu, nothing appears.
Same as point 2.
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