Parametric (adjustable) FreeCAD model of a cylindrical GPU support. You can set the diameter of the bolt, the diameter of the nut, the allowable printing angle without support material, the extrusion of the thread, the vertical thread component, the minimum height of the support, and allowance for nut/bolt fitting. In the spreadsheet, you will see the maximum height based on your minimum height and the solid components.

I understand that there are many Fusion models out there, but FreeCAD – the free alternative – seems to be underrepresented here.

The thread is generously large by default, making printing it with a 0.6mm nozzle easy and the fit snug. My model was printed with nGen, and it supports an RTX 3080 FE.