Sapphire RX 580 does have a ZERO DB Cooling:
Intelligent Fan Control III
ZERO DB COOLING
Enjoy complete silence under light workloads with entirely passive cooling. No spinning fans means no distractions while you work or chill.
PRECISE FAN CONTROL
Traditional fan may have up to 10% difference on fan RPM from fan to fan at the same fan duty cycle. Now with the new fan controller on the SAPPHIRE NITRO+, this tolerance is reduced to 3.2%. This improvement on the accuracy ensures the cooling and noise performance of every card is up to the standard.
Also Sapphire has its own GPU software called Trixx. The latest version is 7.3.0.Users in the past have complained about the same issue about Zero RPM not working. Seems like it was a AMD driver problem with those.
Do you have the latest AMD Driver installed from here: https://www.amd.com/en/support/kb/release-notes/rn-rad-win-20-3-1
In the Release Notes for the latest Driver under FIXED ISSUES:
Also try a previous AMD Driver and see if the fans starts working normally from here: https://www.amd.com/en/support/previous-drivers/graphics/radeon-500-series/radeon-rx-500-series/rade...
NOTE: Sometimes Radeon Wattman has conflicts with 3rd party software like MSI Afterburner and Trixx. Try uninstalling MSI and Trixx and use Wattman to configure your GPU Fans to be aggressive or disable Wattman and any other software that controls the GPU fans and see if Zero RPM starts working or not.
