(relating to AMD gpu's only) If your gpu is being read as 0% in task manager try this,
"You can check which version of WDDM your GPU driver is using by pressing Windows+R, typing “dxdiag” into the box, and then pressing Enter to open the DirectX Diagnostic tool. Click the “Display” tab and look to the right of “Driver Model” under Drivers. If you see a “WDDM 2.x” driver here, your system is compatible. If you see a “WDDM 1.x” driver here, your GPU isn’t compatible."
If u wish to find something that CAN read your gpu usage I recommend using
https://support.amd.com/en-us/kb-articles/Pages/AMDSystemMonitor.aspx