Maybe conductivity is an issue, but I don't see why things should be set up that way. I would ensure that both the heat sink and the top case of the CPU were g

Maybe conductivity is an issue, but I don't see why things should be set up that way. I would ensure that both the heat sink and the top case of the CPU were grounded. I wounld't rely on that ground path, but any conduction along it would be welcome in my world.