Got myself a coolermaster case with 500w psu. The main fan is in a funny position - it's actually on the bottom of the case, pointing towards the floor. Now, the problem is, that the fan makes a (fairly quiet) noise - sort of a scraping noise, but doesn't sound all that bad. If I put the case on its side, it goes away. If I put the case on the carpet (the case does have legs) I can barely hear it, but was advised by the store to put it on a wooden board - but then the noise is pretty noticable. Is this just the sound that most people just put up with? Would it be ok to just leave it sitting on the carpet, since the legs give it a little airflow?