My GPU fans used to spin when I would be running a beefy program. But the other day I bought battlefield 1 and the GPU was at 90°c+ and the fans were not spinning, there is no option to turn them on manually.
Specs:
CPU i5 6600K OC 4GHz
GPU Geforce GTX 1070ti Expedition 4gb
8GB RAM
Specs:
CPU i5 6600K OC 4GHz
GPU Geforce GTX 1070ti Expedition 4gb
8GB RAM