GTX 1080 fans won't spin at all

[Moonphase]

I am going to start this thread by saying yes I know that there is a thing called a fan curve. And yes I have set it to the max rpm and my fans still will not spin.

 

I bought this Gigabyte GTX 1080 brand new back in 2018. About a year later the fans stopped spinning and by the time I noticed it the computer blue screened. Ever since then, the card works, but the fans won't spin at all. Even at startup. I've tested it on at least 5 different PC's and done multiple VGA bios flashes and manually flashed the VGA driver myself multiple times. I have taken the card apart a few times and did not notice and burns or shorts. I even took my magnifying glass and multimeter and tested each resistor, ic, mosfet, capacitor, etc and could not find a short anywhere. I even checked the continuity to ground on all the fan headers on the vc and they all came back with some resistance in the kOhm or so.

 

My next guess is that the fans are shot but the bearings feel fine. Could it have just been the motors going bad? It just feels weird that all 3 fans would go bad unless there was a short.

 

Is there some way I can bench test the fans sepetately without having to plug it into a mobo? Any other suggestions?

[Levent]

They are 12v fans, you can just send it (as long you power the correct pins). You can also probe the fan header to see if you get 12v at all, because since they are PWM controlled 0rpm capable fans, there always should be 12v [I am not too entirely sure if this is the case with GPU fans though]

[Moonphase]

9 hours ago, Levent said:

They are 12v fans, you can just send it (as long you power the correct pins). You can also probe the fan header to see if you get 12v at all, because since they are PWM controlled 0rpm capable fans, there always should be 12v [I am not too entirely sure if this is the case with GPU fans though]

So I was trying to bench test the fans yesterday by starting at 7v and ramping them up to 11v I didn't actually try 12v until today and I saw the fans instantly spin up. Unfortunately only the two outer fans spun up. I then unplugged the middle fan from the harness and the outer fans still spin but then when I plug the middle fan into the power supply I get nothing.

 

Is there a reason that one of the fans would have randomly died? Would this cause all of the fans to not spin up? When I connected the power supply to the harness with all fans connected only the outer fans spin but they still spin. When I had the fan assembly on the gpu none of the fans spun up.

 

Anyone know what might cause this? If it might be something other than just a dead middle fan?

[Godlygamer23]

Are you running the middle fan separately or alongside the outer fans?

[Moonphase]

5 hours ago, Godlygamer23 said:

Are you running the middle fan separately or alongside the outer fans?

I ran it plugged into the harness with the other two fans and only the two outer fans spun up, so I then unplugged it and plugged it into my power source the same way as I did the other tests and it would not spin.

The first picture is how I hooked up my power supply to the fan harness. The grey is the ground and the white is the 12v.

The second picture shows the two outer fans spinning, this was after I had ensured that the middle fan was plugged back into the harness.

In the third and the fourth picture show some additional fan connectors. But these two fan connectors in picture 3 are the connectors for the rgb panels in picture 4.

Then in the 5th picture I unplugged the middle fan from the harness and plugged it into the power supply the same way as the other test. The only difference is that the connector is now a female connector not a male connector which means the pins will be flipped. I turned the power supply on and nothing. I even double checked the voltage before I tested the middle fan.

Is there a reason the middle fan might die like this? or did the middle one just go bad before the other ones? Would something on the gpu pcb cause this to die?

(fyi the pics are real idk why some of them look like Samsung is using some kind of AI upscaling)

Picture #1

Picture #2

 

Picture #3

 

Picture #4

 

Picture #5