| Temperature controlled case fan is in the market long time ago. The characteristic of TC fan is the fan speed varied according to the temperature detected by the temperature sensor. Once it connects with power, it could work perfectly with its TC function. |
TC curve is showing the relation between fan speed and temperature of the fan. Most of the generic TC fan in the market is running a flat TC curve as below. 
The fan speed and the temperature of the TC fan is in direct proportion. The higher the temperature, the faster the fan. The range of variation will be started from 0°C to 40°C 
The steep TC curve showing that fan speed will keep at low rpm below 32°C. The variation is mainly focus between 32°C and 38°C - a critical temperature range in your case. The change of fan speed will be more obvious and effective against the temperature in the real situation. | The best position for the thermal sensor | It is recommended to place the thermal sensor on the top of the PC Case. As hot air goes up, the temperature there is showing the highest ambient temperature inside the case. Therefore, it allows the change of fan speed reflecting the system temperature directly. | Advantage of steep TC curve over the flat curve | 
Great noise elimination
Compare to the generic TC fan, the steep TC curve of advanced TC fan shows a great noise elimination during operation. Normally, the room temperature is at around 24°C and it won’t be as high as 32°C when your computer is at idle. However, a generic TC fan already turns its speed into about 80% of full speed which is not necessary. When the computer is at full load, the fan speed is only move a little bit faster. In the steep TC curve design, the revolutionary programmed temperature controller plays a key role. As shown in the chart, when case ambient air temperature is at safe level 0°C to 32°C, the fan speed remains at its lowest (500 rpm). This is to offer adequate ventilation at the lowest noise level possible. It is therefore completely inaudible (0.05 sone) at low temperatures – a much quieter level than generic TC fans. Rapid respond towards temperature change
Steep TC curve fan is programmed to achieve top fan speed at 38°C. The fan responses to the rise in temperature swiftly – within a critical 6°C range, the rpm of the fan increases from around 500 to its maximum of 2,000 rpm (the steep curve in the chart). Heat is dissipated from the case rapidly in order to achieve immediate cooling. As a result, the case air temperature remains at 38°C or below and thus the possibility of having a system failure can be eliminated. | 
