You honestly can't expect us to help you with what you have just posted, right? Please provide at least some sort of detail - for starters, your system specs.. Second, are the fans hooked up to the motherboard, or the power supply (PSU)? Also, do they support PWM?
If they're hooked up to the motherboard, and support PWM, try using a program like SpeedFan
. If they're hooked up to the PSU, they'll run at 100%.