@gsuberland PCIe spec says 0.7um (micron) gold over 1.2um nickel. This is IIRC enough to last for 50 mating cycles.
Be very careful about units, as PCB plating used to be commonly specified in uin (microinches), and sometimes still is. 1 microinch is only about 0.03 microns, so if you and the PCB company aren't using the same units, you can get screwed.
If you have to use microinches, the equivalent to the PCIe spec is (obviously) approximately 25 microinches gold over 40 microinches nickel.
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