Since the fan settings according to Speedfan are already set to 100% I am thinking there may be either a faulty fan.
SpeedFan can't control the GPU fan.
If you can't control fan speed from the NVIDIA Control Panel, try using a third-party utility.
Please download and install EVGA Precision
. (Click on the Download (America)
or Download (Europe)
link, then scroll down and click on I Agree
Run EVGA Precision. On the right side, you should see Fan Speed
and, beside it, an Auto
button. Click the Auto
button so that it is no longer selected, then change the Fan Speed
. Now, go to the left side, and on the bottom, click Apply