The cool air drawn from the outside of the system will help cool down the power supply which will in turn ensure that the power supply operates at its utmost efficiency.
Control fan speed connected to power supply.
From the motherboard or directly from your computer s power supply.
Bios settings before moving on to any fan speed control software try digging into the system s bios.
Seen in psus is a thermistor bonded into one of the heatsinks.
If they re connected to the power supply usually through a molex connector there s no way to control them through software you d have to hook them up to a hardware fan controller.
The 120mm enermax branded fan eb122512h is controlled to rotate between 450 rpm and 2 000 rpm depending on the ambient temperatures.
Edit nr 2.
If the fan bearings were seizing the fan would not start.
This way it turns on and off at the proper speed when it s needed.
To enter the bios you need to reboot your computer and press a certain key.
Pulse width modulating pwm the fan directly involves turning the fan s power supply on and off at a fixed frequency.
The fans in your computer can get power in one of two ways.
As far as the ramps is concerned there is a spot for a 2 pin header near d2 that breaks out permanently on 12v.
Choosing the appropriate frequency for this method can be somewhat tricky.
If you have room tape another 120mm fan to the bottom of the psu to drive.
Most modern computers already have built in controls there.
It is a 9 blade design and incorporates dual ball bearing and is rated for 0 30a at 12v.
A fan connected this way can be controlled by g code and you can tell your slicer when and how fast to run it.