how are you machining them?
a slotted hole for the amd (53.2mm-54mm) would cover amd recent
but nvidia higher end (470/480/570/580/670/680 series ) would be 58.4
nvidia 460 and 560ti is the odd-ball rectangle 51x61
if youre using a cnc mill, no problem, do them as they are ordered. if not, you will have huge slots for hold downs that will be weak. you would not be able to do full universal.
i wish i had the software and/or know how to plot out the holes in actual size. might be able to do amd slot plus x70/x80 series nvidia on the same mount. special order a 460/560ti mount.
as stated earlier, good luck with your idea.
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