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I recently purchased a 3 wire PSU fan for a project and was trying to power it using a computer power supply but it won't turn on.

I stripped 2 out of the 3 wires because I know the first 2 are the actual power supply wires, and the extra one just telling the motherboard how fast it's spinning. Since I'm using the fan for a hobby project and not for my computer I just ignored the third wire.

I connect the positive and ground to my power supply and all I get is one faint click sound from the fan? The power supply can provide 12V and 10A while the fan is rated at 12VDC and 0.2A. I don't think this should be a problem because I'm not forcing too much current? The fan can draw as much as it needs and the power supply just goes up to 10A.

https://www.youtube.com/watch?v=1UgoiEsoMzU It managed to work in this video.

Not sure what the problem here is so if anyone could help it would be great. Did I fry my fan somehow? Thanks in advance!

enter image description here

P.S I'm pretty sure I wired it correctly because the striped should be positive and the wire with lettering is ground. Image above are the three wires for reference.

EDIT: The fan is part of a cpu cooler with a part number of SE-902-SD

enter image description here

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  • \$\begingroup\$ You should edit to include the fan's part number and link to datasheet. What is the photo supposed to show us? 'V' for volt. 'A' for ampere. \$\endgroup\$
    – Transistor
    Jun 5, 2021 at 8:36
  • \$\begingroup\$ I just edited my post \$\endgroup\$ Jun 5, 2021 at 8:39
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    \$\begingroup\$ sure that's actually an output, and not a PWM input, your third cable? \$\endgroup\$ Jun 5, 2021 at 11:14
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    \$\begingroup\$ Can you double check how you connected it? If you mean that you connected ground to middle wire with text, and 12V supply to striped wire at the edge, you have connected the power supplies the wrong way around. Motherboard fan connector pinouts have +12V in the middle, and GND at the edge (pin 1). The other edge has the tachometer output. \$\endgroup\$
    – Justme
    Jun 5, 2021 at 12:13
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    \$\begingroup\$ OMG that fixed the problem Justme, welp I feel pretty stupid for not have trying that. Thanks so much! \$\endgroup\$ Jun 5, 2021 at 12:25

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The power supply connections are applied wrong.

+12V is the middle pin on PC motherboard fan connectors.

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  • \$\begingroup\$ Thanks again! I just wrongly assumed the connections because that's how I did it in another project. \$\endgroup\$ Jun 5, 2021 at 14:25

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