Is the dial actually to control the fans? It really depends on your motherboard and how the fans are connected. It also depends on your bios. Have you had the case open and if not, are you confident enough to do it? My first advice is if it is a new computer, go back to the supplier and ask them to help. If this is not an option, look inside the case. (Get a more technical friend to help, if you feel this is not something you would want to do). If the fans connect directly to the power supply via molex connectors (red black and yellow wires to a flat white plastic plug) then they are not controllable, and run at full speed from the power supply. If they plug into the motherboard, then they are most likely, but not necessarily controllable, but not directly. The way they work is this. Sensors on the motherboard read the temperature, and which temperature they read and how they read them varies greatly between motherboards and bios systems. If the fans are controllable, a chip in the motherboard will speed up or slow down the fan accordingly. Why? You might ask. The reason is to use less power when the components do not require optimal cooling. You will need to know where these fans plug into the motherboard. The manual that came with the computer or motherboard should tell you how to do this. It may be on an installation cd. You could �Google� the motherboard for an online manual. I still think, if it is new you should go back to the supplier for advice and assistance. If I am not making myself clear (what seems easy to me may be a technical minefield to you! This does not reflect on your ability or intelligence. It is merely a matter of experience.) please post back and I will try to help.