SpeedFan

SpeedFan is freeware that looks at motherboard and hardware monitoring and allows you to take control on the speed that the fans on your hardware. This allows for better cooling and less noise in general. It can access status information via S.M.A.R.T. data from EIDE, SATA, and even SCSI drives. Need to know how much voltage and what the temperatures are? Just check it out. Windows only.