Ruth's sister
Ruth's sister USB to 4Pin fan adapter cable 30cm 5V to 12V
Converts a 4-pin chassis fan to USB power with a 30 cm, 22 AWG copper cable, reducing fan speed by 60 percent
- Powers 4-pin chassis fans from any USB port
- Steps 5 V up to 12 V for fan operation
- Pure-copper 22 AWG conductors rated to 80 °C
- Compact 30 cm length with 3.5 mm outer diameter
- Reduces fan speed by 60 % for quieter running
USB to 4-pin fan adapter cable
This 30 cm cable connects a standard 4-pin chassis fan to a USB port, converting the 5 V supply to 12 V for the fan motor. It uses 22 AWG pure-copper conductors with PVC insulation and an outer diameter of 3.5 mm. The assembly weighs 11 g and is rated for 80 °C operation.
Suitable for low-speed cooling mods.
Makers who want to run a case fan from a laptop or power bank will find this adapter simple and compact. Builders who need full fan speed or PWM control should look elsewhere, because the USB supply cuts rotational speed by roughly 60 percent. The fan must also support 5 V low-voltage start-up, otherwise it will not spin at all.
60 percent speed reduction is the deciding spec
Using this cable drops fan RPM by about 60 percent compared with a direct 12 V header. If the application can tolerate significantly lower airflow, the adapter works; if the cooling target demands full-speed operation, this part will not meet the requirement.
Highlights
- Powers 4-pin chassis fans from any USB port
- Steps 5 V up to 12 V for fan operation
- Pure-copper 22 AWG conductors rated to 80 °C
- Compact 30 cm length with 3.5 mm outer diameter
- Reduces fan speed by 60 % for quieter running
Specifications
No published specifications for this item yet.
Questions about this item
Does the 5 V USB supply make the 4-pin fan run hotter or louder?
The adapter steps 5 V up to 12 V, but fan speed drops by 60 %, so noise and heat output are lower than at full voltage.
What must I already have for this cable to work?
A chassis fan that can start and run at 5 V low-voltage; otherwise the adapter will not spin the fan.
Will the 30 cm length reach a rear case fan from a front-panel USB port?
At 30 cm the cable suits short runs — typical for laptop cooling-pad conversions or internal USB headers near the fan.
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