Don't believe this is a setup issue. I am running TightVNC 2.8.63 on Intel i5 Quad Core running Win10 Pro version 20H2 using a graphics card running AMD Radeon HD 7700 graphics. When connecting to system remotely using TightVNC viewer, I get black screen displayed. I removed TightVNC service from this PC and installed UltraVNC in its place and was able to see the desktop screen remotely using TightVNC viewer on remote computer. This has been a problem for some time, just hadn't reported it. I am also able to access the same computer remotely using Remote Desktop as well.