Question Only one GPU fan is on when I boot up my computer, then slows down when I open and play a game for a bit

[NimbleOrange]

When I boot up my PC sometimes everything is normal and and do whatever I was planning on doing but a lot of the time I turn it on and only one of the 2 fans on my RX 580 is spinning, at max speed. Usually I open up a game like Rainbow Six Siege, play it for about 5 minutes and the other fan turns on and both run at normal speeds.

The thing is when I look at any programs that tell me the fan speed of the GPU they always say 0 RPM when one of the fans is obviously running very fast.

Any ideas? (I've tried uninstalling and reinstalling all the drivers and I've checked for and debris in the fan)

 

[Metal Messiah.]

Kindly provide FULL PC specs, including the make/model number of your Power supply and motherboard.

 

[NimbleOrange]

CPU: AMD Ryzen 5 2400g
GPU: Sapphire RX 580 4GB
Motherboard: Asrock B450 Pro-4
PSU: Corsair 650w (can't remember full name but it's semi modular and 650w)
RAM: Corsair Vengance 2x8gb 3000Mhz