SpeedFan is a freeware program that monitors fan speeds, temperatures and voltages in computers with hardware monitoring chips. SpeedFan can even access S.M.A.R.T. info for those hard disks that support this feature and show hard disk temperatures too, if supported.SpeedFan supports EIDE, SATA and SCSI drives.

Changelog

Speedfan 4.46

Speedfan homepage