Gigabyte Siv Fan controll

[WhiggaD]

Hi guys, so im using the Gigabyte gaming 7 Mobo with an i7 6700k and this cpu cooler.
Although these fans have a minimum of 800 rpm i could change in Siv the fan which is connected to  the Cpu OPT to  a minimum of 345 prm, wanted to reduce noise.
Now i want to change the other fan which is the same to around 500 rpm or less, but as you can see in the pictures its not possible.Any suggestions?
Thank you.

[shadowsports]

Based on the limited information you provided, is it possible that one or more of the fans does not support the speed threshold you are attempting to set?

What size are the fans you are controlling?

If you make conflicting settings in BIOS, SIV will not allow you to control fan speed in the OS as you might expect. 

[WhiggaD]

Based on the limited information you provided, is it possible that one or more of the fans does not support the speed threshold you are attempting to set?

What size are the fans you are controlling?

If you make conflicting settings in BIOS, SIV will not allow you to control fan speed in the OS as you might expect.

They are the same with 800-1500 rpm, 120mm fans.
I checked speed in Bios now, its different than SIV shows me, although 1 fan is still under 800rpm.