SpeedFan is a program that monitors voltages, fan speeds and temperatures in computers with hardware monitor chips. SpeedFan can even access S.M.A.R.T. info and show hard disk temperatures. SpeedFan supports SCSI disks too.
SpeedFan can even change the FSB on some hardware (but this should be considered a bonus feature). SpeedFan can access digital temperature sensors and can change fan speeds accordingly, thus reducing noise. SpeedFan works fine with Windows 9x, ME, NT, 2000, 2003, XP, Vista, Windows 7, 2008, Windows 8, Windows 10 and Windows Server 2012. It works with Windows 64 bit too.