Kind of a "which students" sort of question. I'd say with the older ones. With those, you can put a logic analyzer on the memory bus and see what's going on -

Kind of a "which students" sort of question. I'd say with the older ones. With those, you can put a logic analyzer on the memory bus and see what's going on - if the pins aren't on a BGA under the chip and the board has no vias.