Advertisements Pots are stupid. They are essentially coils of wire. The only way they slow anything down is by converting current into heat. They are essentially Resistors that can be adjusted. They can't make a fan run faster, only slower - and yes, quieter. So if you start with a fan that is more than adequate for cooling, but is noisy, and then slow it down with a pot, so everything is quieter, but still cool enough - the pot has done its job. But that's the only thing it can do.