I'm very new to 3D modelling so I thought I'd start off with something very simple that I made in FreeCAD. It's a GPU bracket to stop sagging which could potentially destroy your PCIE Slot on your motherboard, I hope it can help in some way!

I've printed mine with PETG, 15%, Supports On and it came out fine and does the job for me! I assume it would print out fine with other materials and settings but any kind of constructive criticism or recommendation would be greatly appreciated :)