Breaking down a circuit board for precious metals is a time-consuming and expensive process especially since only the gold is recoverable. You can expect to get a fraction of a gram of gold from the average motherboard and far less from secondary and tertiary boards. In addition, the recovery process can release dangerous chemicals and particulate matter into the air that can damage your lungs and eyes. This will not make you rich quickly, or even rich at all. Instructions 1 Put on your safety goggles first, then put on a full-enclosure air mask. This might seem redundant, but commercial grinders (also referred to as mills) exert larger amounts of pressure on the circuit boards and pieces can be flung off with high velocities. The air mask also is necessary because of the cloud of dust that will be expelled during the crushing process. Gloves are just to prevent cuts from the circuit boards as you load them. 2 Plug the commercial grinder into a 240-volt outlet. Turn the safety lock to on, then run the grinder for a few minutes if this is your first time running one. This is to ensure the crusher teeth are properly aligned and not hitting each other. Arrange the circuit boards in bundles no bigger than a foot tall, securing them with string. 3 Toss the circuit boards in the top of the grinder, allowing for two to three seconds to pass before tossing in the next bundle. Continue to toss in bundles so long as the status light remains green. If the grinder gets stuck or turns yellow, then engage the reverse gears to expel the stuck pieces. If it is necessary to remove a piece, only do so with the grinder off and the safety lock on. Do not reach in with your hands. Only use a scrap piece of wood. 4 Turn the grinder off, and take the collection basket out when you are done grinding. Pour the ground-up circuit board through a metal filter into a coffee can. The metal parts will be caught by the filter as the plastic parts of the circuit board fracture into dust under the pressure of the grinder. Pour the metal parts onto a pan, and pass a magnet over the parts. Pure gold is not magnetic, so it should only pick up the ferrous metals. 5 Shift through the remaining metal pieces, looking for shiny, yellow pieces. These pieces will be gold, and can be sold at many metal brokers and jewelers.