Answers as i know them.
1. The square ones with the metal fingers around the 4 sides are wat people call flatbacks. Thesquare ceramic grey looking ones are more like a CPU.
2. No any chip that looks like these even if they are soldered to the board are eproms.
3. Depends on buyer. I only pull the ones that can come off without tearing up the board. So far no downgrade from the people ive sold too. Now I know if I took every single one of them off they would surely downgrade it.
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