Ah I was thinking of thin flat strip of wood. Thanks for the warning. Then wood and metal are both ruled out. I would love to build a crate rig like the one you pointed me to (thanks) but I just don't have the time now + my need to be operational is more urgent. Once I am operational, I want to take my time and build a proper rig.
If we are looking at rod shapes, can I use think plastic pipes used in plumbing? I can figure out a way to secure the rods to the case, what about the gpu to the pipes. Should I do that too?
Basically any plastic pipe, rod, or what-have-you that can be secured and will support the weight of the GPUs would work.
Zip ties or Velcro straps can secure the ends of the GPU at the bracket on one end (you can make a nut and bolt anchor using the bracket fastening holes if it suits your fancy).
Often times there is a small hole in the PCB that can be used on the other end but be careful as you don't want to stress the PCB. Depending on the cooling system the GPU has there may be other viable anchor points on the non-bracket end. You can also gently tie down the PCIE cables to the support and the wire tension will provide stability as well.
Of course this setup is not earthquake proof but should be jostle safe. I have two 7970s in a crate doing it this way.
