External GPU Riser Stand (Mining with PCI Riser)

This is a new version of External GPU Stand to be used with a PCI Riser. It's an improved version from https://www.thingiverse.com/thing:2728879.

The improvements are:
- Less printing time and less material required while maintaining the same structure and rigidity
- No more 90 degrees overhangs, with this version any printer will be able to print successfully without supports
- You have the option of using a self tapping M3 bolt, a nut and bolt or even use an insert to secure the GPU
- Smoother contours and better triangle arrangement to improve printing time

Please, if you have any suggestions, let me know.