Hello, I have a Quadro RTX 4000 graphics card with a FAN problem.

The fan immediately spin up to 100%. I checked the TACH pin on the fan connector, and there is a direct short(44Ohm) to ground. With the fan disconnected, the short is still present, so the issue is on the PCB, not in the fan itself.

I traced the TACH line and checked the nearby pull-up resistors — they all seem fine. There are no visible burned components. Close to the fan header there are chips like NCP45491, uP9512R, and uP1666Q, but as far as I know, they are VRM/power monitoring controllers, not...