Most DC computer fans are designed to operate on a standard voltage, typically 12 volts (V). This 12 - V standard is widely used in computer systems because it is the voltage provided by the power supply unit (PSU) through the motherboard's fan headers. what changes is the current (measured in Amperes). Here are the common operating voltages for DC fans, including the notable 48V category, along with their typical use cases: Application: Small USB-powered fans (e., desktop USB fans, mini cooling solutions for. As far as I can tell, based on my mobo manual (Page 34 always), the only fan header that supports PWM is the CPU fan header, and the header supplies up to 12V to the CPU fan. The mobo supports 4 additional system fans in DC mode with an unspecified voltage. They require a higher voltage than the axial and radial fans and operate at 48. Brushless DC fans are usually available at three nominal voltages: 12V, 24V and 48V.
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