You have an Asus K75VM
laptop which has an Intel H76 chipset
. The mobile version of this chipset has no fan control outputs so you do not have the necessary hardware for software fan control under any operating system.
Your fan speed is controlled by your BIOS. YouIt sounds like it is working as intended as 50 degrees Celsius is a normal temperature for a laptop CPU. If you want to tune the fan or power management setings you can probably tune thisfind these under the advanced settings
page of your BIOS.
laptop-mode tools
and tlp
do much more than attempt to control the fan speeds. Install one or the other but not both.