I've just built my own pc its an e6600 cpu, abit ab9 mobo, 7900gto gpu, and 480watt xclio psu. i have a coolermaster centurion 532 case with space for two 120mm fans. i curruntly have 2 coolermaster fans but i'm looking to replace these with quieter ones. they are rated as 22dBA and move 43 cfm of air. the system runs relativly cool all <40 degC. Does any one have any recommendations. Thanks.
Generally Coolermaster fans are pretty quiet. Are you sure that's the source of your noise? Try disconnecting the power to your case fans (no harm will be done for a few minutes). That will give an upper limit of how quiet you can get. You may find the the real source of your noise is your CPU or GPU fan.
If you do decide to replace your case fans here are two facts and one unfortunate conclusion:
Fact1: Fan noise ratings have more specmanship than just about anything else.
Fact2: Loudness is objective. Noise is subjective. Your may be fine with a tick, but hate a rumble; or vice versa.
Conclusion: You will probably buy one or two more fans than you actually use.
Well if you want silence then, increasing the airflow inside your computer case thus helps. You should place a good fan on the side panel as well as that mesh hole that is below it. So now you have 2 fan taking in more cool air and blowing towards the cpu and gpu. That way, the more low-rpm fans you are using the quieter it can and still manages to have a good airflow.