80mm or 120mm Fan For Side Panel? Or two?

[DAnDan]

I'm just about the swap all the fans on my case for new ones, as the current ones are far, far too noisy for me.

I have the choice or 1 or 2 fans on the side panel of my case, either 120mm, or 80mm. Are 120mm fans generally noisier, or quieter than 80mm ones?

I have the zalman fan controller, so I can always change the speed to suit the needs. I'm thinking a 120mm fan at a low speed may be more effective/noice friendly than a 80mm one going faster to move the same air?

Or 2 120mm fans at a very low speed?

 

[DAnDan]

I've already payed for the fan controller, and honestly I like the idea of being able to control the fan speed for the occasion.

So 120mm fans are the way to go then? Thanks