[SOLVED] Blower card expelling air out in front of the fan instead of out the back

May 22, 2020
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I have a gtx 960 and lately its been running very hot, 99-102 C on loads, and around 60 idle. I thought it was the thermal paste so I changed that and cleaned the dust out the channels but still nothing. When I put my hand near the back where I should feel hot air coming out, I feel nothing. Instead, When I put my hand in front of the fan where air should go in, I feel it getting blown out onto my hand. is the fan spinning backward or something?
Edit: <Mod Edit>, I just realized I posted in CPU not Cooling. any way the change it?
 
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Solution
Reverse a fan's direction by plugging in backwards? Depends on the fan design. Almost all computer fans today are of the brushless design. The fan has no traditional commutator or brushes for switching the current to sequential poles of the rotor. Instead it has a small circuit board that switches the current to the sequence of field coils positioned around the rotor, and the rotor actually has the permanent magnets, not the field coils. For that type of fan, plugging in backwards will result in a fan that does not turn, because the circuit board is getting its power all wrong and cannot do its job.

HOWEVER, the older style of simpler DC motor up to maybe the 1990's DID use a commutator on the shaft of the rotor, feeding a sequence of...

Paperdoc

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Reverse a fan's direction by plugging in backwards? Depends on the fan design. Almost all computer fans today are of the brushless design. The fan has no traditional commutator or brushes for switching the current to sequential poles of the rotor. Instead it has a small circuit board that switches the current to the sequence of field coils positioned around the rotor, and the rotor actually has the permanent magnets, not the field coils. For that type of fan, plugging in backwards will result in a fan that does not turn, because the circuit board is getting its power all wrong and cannot do its job.

HOWEVER, the older style of simpler DC motor up to maybe the 1990's DID use a commutator on the shaft of the rotor, feeding a sequence of coils mounted on the rotor. These faced stationary permanent magnets mounted around the rotor in the fan frame. A pair of metal fingers or "brushes" pushed against the turning rotor and commutator to switch which rotor coils were energized and cause it to turn. On THAT type, simply reversing the power supply lines to the motor DID cause it to turn backwards.

So, OP, try to change the video card fan's connection to its power pins on the card and test for a short time. If it fails to start, that may be the wrong way. But if it starts up and blows the right way, you have your solution.
 
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