Before criticizing a software you have not tested, read its description. Today, there is NO free alternative for iMac 2009-2011 when you want to replace its hard drive. The fan runs at full speed.
It is doing what smcFanControl is not able to do: controlling the fan speed according to the temperature data sent by the hard drive or the SSD drive. If the temperature rises, the fan speed rises consequently. It is not a static speed, but a dynamic control. It works at the very startup, before the login screen appears.
It is doing what smcFanControl is not able to do: copying the behavior of the Apple proprietary hard drive firmware in all iMac 2009-2011. Blame Apple for that. Either you upgrade your iMac hard drive for 50$ for a 1TB + 30$ for HDD Fan Control, or you by a genuine apple's iMac drive at 300$ with its proprietary firmware.
[Version 2.0]
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Bracketeer
Vaxxoz rated on 13 Sep 2011
[Version 4.3.5]
+4
HDD Fan Control
Vaxxoz reviewed on 04 Jul 2011
It is doing what smcFanControl is not able to do: controlling the fan speed according to the temperature data sent by the hard drive or the SSD drive. If the temperature rises, the fan speed rises consequently. It is not a static speed, but a dynamic control. It works at the very startup, before the login screen appears.
It is doing what smcFanControl is not able to do: copying the behavior of the Apple proprietary hard drive firmware in all iMac 2009-2011. Blame Apple for that. Either you upgrade your iMac hard drive for 50$ for a 1TB + 30$ for HDD Fan Control, or you by a genuine apple's iMac drive at 300$ with its proprietary firmware.