[URGENT] How do I adjust fan speed in BIOS?

Hey everyone,


My CPU is REALLY loud, I could hear is roaring from my bathroom next door.

I have the AMD Phenom II X4 955 black edition.

My MOBO is ASrock M3e770de board.


I checked Speedfan and my CPUFan is running at 6750 RPM.

I haven't touched BIOs yet, like how slow should my CPUFan be at.

Also I heard about the Cool'n'quiet option? should I enable that as well?

How much can I slow down the fan without having it heat up and fry my CPU?


Please tell me what ALL I should do before I close my PC and go into BIOS


I have not Overclocked yet.

=

HIS Radean HD 6850
1 TB HDD
AMD Phenom II X4 955 Black edition
Asrock M3e770de MOBO



EDIT: I have a stock fan! If an after market cooler is less noisy, please list some bang-for-the-buck coolers! Also I have the Thermaltake v3 case, The space is VERY LIMITED so please let the cooler be smaller.

PLEASE STILL LIST HOW TO SLOW DOWN THE FAN, If it's still too loud I'll consider about buying an after market cooler