PC case fan - supposed to be LOUD?

I have a 120mm 75 cfm fan running of a 12V adapter, but it's louder then my 6" desk fan. As in, loud enough to wake you up if it turns on while you're sleeping. But it's only supposed to be 30 dB. WTF?

The airflow is quiet, but the fan itself is making a high pitched humming noise. Is that normal for this? this is the model:

futureshop.ca/catalog/proddetail.asp?logon=&langid=EN&sku_id=0665000FS10099820&catid=10477#
http://www.futureshop.ca/catalog/proddetail.asp?logon=&langid=EN&sku_id=0665000FS10099820&catid=10477#

weedidas said:

I have a 120mm 75 cfm fan running of a 12V adapter, but it's louder then my 6" desk fan. As in, loud enough to wake you up if it turns on while you're sleeping. But it's only supposed to be 30 dB. WTF?

The airflow is quiet, but the fan itself is making a high pitched humming noise. Is that normal for this? this is the model: http://www.futureshop.ca/catalog/proddetail.asp?logon=&langid=EN&sku_id=0665000FS10099820&catid=10477

Click to expand...

not sure, but if i am playing a game on my PC that is graphics heavy, the fan on the video cards screems. I assume this is because max voltage is being applied to it. If you decrease the voltage on a dc fan, the rpm's go down along with the noise.