Radeon VII doesn't incorporate Zero RPM feature. So the fans will be running all the time. Should be running slowly under Idle conditions and faster as the card get hotter.
Are you concerned because of the Noise or trying to save electricity?
From Tom's Hardware Review on Radeon VII: Fan Speed and Noise - AMD Radeon VII 16GB Review: A Surprise Attack on GeForce RTX 2080
And to elaborate on that, if you turn off hardware acceleration in your browser, your GPU won't be under any load large enough by the browser to require it to spin faster than that.
They way I solved the issue is to grow old, and start to go deaf. Thus, the volume needed for me to hear any video easily drowns background noise.
I'm actually more concerned with dust build up and "oxidization", which will occur much much more often with the fan spinning even at 800rpm-ish. Most if not all AIB partners incorporate zero rpm mode for their GPU.
Makes me want to jump back to AIB board JUST for the zero rpm, but that means I will have to settle for a lower end 5700 XT, UGH.
I know there is an argument that zero rpm mode actually worsened the life of the fans because they have to keep starting and stopping. The thing is, majority of the time I don't game...
I had a STRIX VEGA 56 previously, that card was huge, but it ran passive fine even running 4k videos on MPC-HC...