If for free take it. If for cash thenoffer 1/4 the price of boardsort then you can still profit. If this offer is refused then go get free computers. "Decent" amount of PM is relevent to the amount you pay for the ram and how much chemicals and time you want to put into getting PM's out.
20+16=36
say about 700-750g three quarter of a kilo so there might be about 2-3g on fingers, stick with 2 it is better for calculations.
Maybe (and I mean it MAYBE) about additional gram in chips. Depend on how many are there.
No Geo I would say more but I have no idea how many chips are there on his RAM sticks so I just went for minimum. I do not want to mislead him.
That was just a guess that is why I said maybe.
I would say that on RAM chips you look at minimum 2g/kilo. There will be some silver and Pd bonus in there too.