Most PCIe riser boards come with a foam mat on the bottom. However if you prefer to fasten it to your rack/wood beam; then you can use this with zip-ties or screws to give your PCIe slot horizontal stability.
Most, if not all, riser boards to my knowledge have the same screw hole format. So they should be able to screw right into this stand-off once you fasten it down. If you are concerned, then these are the exact ones that I used with this print.
https://www.amazon.com/gp/product/B0769VZ5Q2/ref=oh_aui_detailpage_o06_s01?ie=UTF8&psc=1
| pcie_riser_board_w-holes.stl | 83.9KB | |
| pcie_riser_board_wo-holes.stl | 58.3KB |
