Many people do not realize that their computer actually has a wide array of sophisticated sensors that keep tabs on all sorts of real-time environmental data inside the PC. Voltages across various circuits, fan speeds, and internal PC temperatures are only the beginning of what many hardware monitor chips can track. S.M.A.R.T. data, along with the temperatures inside the hard-disk drive, are also available with the right software. SpeedFan is a software package that allows users to do this.

SpeedFan is a versatile software package that helps computer users monitor the performance and environmental variables inside their computers. It works by accessing the data from the hardware monitor chips, hard-disk drive firmware, and other chip-based sources. SCSI disks are not a problem for SpeedFan, and it is also capable of accessing S.M.A.R.T. data.

For some machines, the front side bus (FSB) can even be accessed and changed using SpeedFan, allowing users to overclock their PCs, resulting in enhanced system performance. However, this option is not available on all machines because some processors do not support software access to the FSB. Check the literature from your CPU's hardware vendor for details on whether or not your PC's processor supports changes to the FSB for overclocking purposes.

The operating speed of fans inside the PC, as well as digital temperature sensors can be accessed by SpeedFan. Not only that, but SpeedFan can even change the current speed of fans in the machine, increasing cooling when needed and decreasing noise during idle times. This is a great option for people who want high performance with less noise. SpeedFan is capable of accessing and controlling the System Management Bus, and it works with all versions of Microsoft Windows up to Windows 7, including 64-bit systems.