CPU fan speed

hi


on this
gigabyte 785gt-ud3h MOBO +phenom ii x4 955

i have evercool cpu fan , it was 1670~ RPM by default

as much as i understand mine fan speed was below below below the average , which is 4000~+- RPM

because i was trying fix some freezing i have i changed in the BIOS the auto speed, see if it was chocking the CPU

than it runs on 2100~

i dont see much diffrence in the speed so , nor i see the reduce in heat , but due to the fact mine fan running below the avearge i think i will leave it as it

so is the fully speed of fan is 2100~(how can it be known?

is it normal?


her pics before changing:

http://img40.imageshack.us/g/80533759.jpg/

after changing:

http://img96.imageshack.us/g/73821482.jpg/

if you look on the pics what mean the temp 1, 2,3? i guess its the sensors of the mobo right?