SpeedFan 4.39 Beta 7 is a Diagnostic Software product from almico, get 4 Stars SoftSea Rating, SpeedFan monitors fan speeds, temperatures and voltages in computers with hardware monitoring chips. It can even access S.M.A.R.T. info for those hard disks that support this feature and show hard disk temperatures as well. Its main feature is that it can control the speed of the fans according to the temperatures inside your PC, thus reducing noise and power consumption. It can even set the FSB on some motherboards.
SpeedFan is a software that monitors voltages, fan speeds and temperatures in computers with hardware monitor 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 SCSI disks too. SpeedFan can even change the FSB on some hardware (but this should be considered a bonus feature).
At the lowest level, SpeedFan is a hardware monitor program that can access digital temperature sensors, but its main feature is that it can change fan speeds (depending on the abilities of your sensor chip and your hardware) according to the temperatures inside your pc, thus reducing noise.
Several sensors, like Winbond's and the AS99127F support fan speed changing, as well as others from Maxim, Myson, Analog Devices, National Semiconductor and ITE, but the hardware manufacturer must have connected the relevant pins to some additional, yet trivial, circuitry.
This means that if you have, say, a Winbond W83782D on a BP6 then you're ok, but not every motherboard with such a hardware monitor chip will be able to change fan speeds. From one of the very first hardware monitor chips that could be found in standard PCs, the National Semiconductor LM75 (and all of its clones, like the Philips NE1617 and the Philips NE1618 or the Maxim MAX1617) or the Analog Devices ADM1021, such chips have been outstandingly improved, both in their precision and in their abilities.
Current chips can monitor fan speeds, voltages and change fan speeds by using PWMs (Pulse Width Modulation). Some chips can even be programmed to vary fan speeds without any additional program intervention. If your BIOS was programmed to setup such chips this way you can still try to use SpeedFan's Advanced Configuration to revert to manual (software controlled) mode. Winbond W83697HF, Analog Devices ADT7463, SMSC EMC6D102, ITE IT8712F, National LM85C and Maxim MAX6650 are very good candidates.
Some SuperIO chips include temperature sensors too. SpeedFan can automatically detect them and use their features. SpeedFan can find almost any hardware monitor chip connected to the 2-wire SMBus (System Management Bus, a subset of the I2C BUS) Serial Interface and to the ISA BUS and works fine with Windows 9x, ME, NT, 2000, 2003 and Windows XP. It works with Windows 64 bit too. It can be minimized to the tray and is compatible with Motherboard Monitor 5.
SpeedFan monitors temperatures, through available hardware monitor chips which expose their temperature sensors connected to different places inside your computer, and, according to your setup, does its best to keep them at your desired value. You can even change a fan speed according to the temperature of your hard disk. When choosing parameters for the minimum and maximum fan speed, try to set them by hand (disable all the VARIATE FANs checkboxes) and listen to the noise.
When you hear no noise from the fan then you can set that value as the minimum fan speed for that fan. I suggest using 100 as the maximum value, unless you hear a lot of noise from it, in which case you might reduce the maximum speed to 95 or 90. Obviously, nothing says that you can't set 60 as your maximum value and, sometimes, I myself set it that way. Consider that when the WARNING temperature is reached, the software sets the fan speed to 100, whichever maximum speed you set. One last word should be said regarding the USE FAN x listbox. In my pc, more than one temperature changes when a fan runs faster. You can say on which fan every temperature should rely. On my system, TEMP1 and TEMP3 are both influenced by FAN1.
SpeedFan can:
handle almost any number of South Bridges
handle almost any number of hardware monitor chips
handle almost any number of temperature readings
handle almost any number of voltage readings
handle almost any number of fan speed readings
handle almost any number of PWMs The license of this windows utility software is Freeware, you can free download and free use this Windows Utility software.