Sapphire GPU Card has an automatic Fan Controller built into it called Intelligent Fan Control II. The Fans turn on when it reaches a certain temperature. The GPU Fans should turn on when the computer starts but once it logs into Windows the GPU Fans should stop unless it was at a temperature where it would be running. The GPU fans, I believe can be controlled with a 3rd party fan controller like Wattman. The new version of Trixx 3.0 also can control when the fans start and stop. But Trixx may have conflict with AMD Wattman when installed. : Request Rejected
Also you have an under powered PSU for the Rx 470 according to this website: PSU REQUIREMENTS - RealHardTechX :
You should have a minimum PSU of 450 Watts for your computer system using a RX 470 GPU Card. But if your computer is booting up normally and you are not having any type of weird symptoms or BSODs then that probably indicates you are not exceeding your PSU wattage when using the RX 470. But if you notice that your computer is crashing when under heavy loads like playing a graphic intensive game, then you may want to check your PSU outputs to see if it is normal.
Nothing is wrong. That's the normal behavior for that graphics card.
thank you very much ON good advice