So, my location dictates a different processing method than the "norm". While not answering the op question directly, maybe my situation will give some direction to this problem.
For me, the price paid for small socket motherboards is almost identical to the price per pound I pay to ship to a buyer. So why do labor for no profit? Removing chips with known pm content without dealing with the board itself leads to a concentration that is profitable.
I understand that many are better off going for total weight with minimum labor, however in my case that equals no profit.
Ewaste is a numbers game, but you need to know all your numbers to win (profit). And as always, the older stuff contains more oz's of .......... per ton (?). Make your decisions based on your numbers, not others opinions. It takes work, experiments, samples, test lots, etc, based on your location, supply situation, overhead and whatever to make a profit. It doesn't matter what others do, determine what it takes for you to profit and proceed accordingly.
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