SpeedFan 4.45, Suported OS: All windows OSs If you need a tool that can change your computer's fan speeds, read the temperatures of your motherboard and your hard disk, read voltages and fan speeds and check the status of your hard disk using S.M.A.R.T. or SCSI attributes, then you came to the right place. SpeedFan works under Windows 9x, ME, NT, 2000, 2003, XP, Vista and Windows 7. SpeedFan works fine on 64 bit too. SpeedFan can access status info from EIDE, SATA and even SCSI drives, consistently showing internal data that can be used to diagnose current and future hard disk failures. This is known as S.M.A.R.T. (Self-Monitoring Analysis and Reporting Technology). At the lowest level, the SpeedFan hardware monitor software can access digital temperature sensors, but its main feature is its ability to control fan speeds according to the temperatures inside your PC, thus reducing noise. But you should always remember that no program can be perfect. So be careful because if you use SpeedFan wrongly then it can cause damage to your system.