Hi PSCO
Sorry for the delay. Is Asus AI Suite still installed? The type of fans connected will also make a difference in how you set them up. ie if they're 3 or 4 pin connector's.
I have a similar bios to you but see you have your's set to EZ mode which i'm not too familiar with. What i do is set my fan profile's in the bios as once set i never need to worry about them again.
If you click on Exit/ advanced mode in the top right of the bios screen in your screenshot to switch to the advanced view. You will now have 6 tabs across the top of the screen, Select the Monitor tab where you have 2 options for fans. Monitor and control Go to control and select either cpu, cha, or opt fan control (Whichever fans you wish to control). I maybe wrong with the exact wording so i appologise now.
If its your cpu fan you want to control select enable from the drop down box. Then select the fan profile type from the 3 options. Silent/ Standard/ manual and Turbo. Standard is fine unless you need to use a faster one in which case select Turbo.
You can also select manual and then create your own profile.
You can also set the lower speed of the fans too. I set mine to 600rpm. Now i'm not sure if this actually sets the minimum speed of the fans or just warns you if the fans drop below the set number as my fans never drop below 700rpm.
I would advise to totally uninstall Asus AI Suite though as it is well known for giving false readings and even some Asus reps advise its removal. If you only use it for monitoring your system then i would suggest using either HW Monitor that i linked before or my favourite HWINFO
HWiNFO, HWiNFO32 & HWiNFO64 - Hardware Information and Analysis Tools
Note, These are only for monitoring your pc and not controlling anything.