Honestly, if the header pins are tarnished or slightly worn as Nino said, they need to be replaced. If you replace the header pins then you need to replace the pins in the connectors as well. Relatively pointless changing one and not the other. The machine came good when you started re-seating connectors which points to replacing them. They are simply one thing you can't skimp on if you want a reliable machine for years to come. It is tedious and time consuming work but the enjoyment you get out of knowing the machine is going to work when you turn it on is well worth it. There is nothing worse than playing a game and not knowing if and when it is going to fail on you.
