Why my coolermaster 120 jet flo won't run at full rpm (CONNECTED AT 4 PIN AT MB)

[distrot]

So i have 3 coolermaster jetflo 120 fans.One at bottom intake one at back exhaust and one at the front top of case as exhast.My back and top front spins at full rpm connected at 3 pin sockets at my mobo.My bottom spins at 1300 +- rpm connected at 4 pin socket at my mobo.The socket writes sysfan.
Any clue what should i do to have the front bottom run at full rpm?
Thanks.

 

[ATMINSIDE]

Did you go into the fan control settings of your BIOS and change the sysfan?

System specs will go a long way here...

 

[distrot]

I found it. My bios setting had enabled the sys fan auto. Ok