Goodness gracious Wookie. Try replacing the upper case first. If that doesn't work, try the logic board. Don't waste your time with Apple. Their replacement parts are super overpriced.
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You may need to remove the heatsinks on the logic board, but while you're at it, you might as well replace that stock thermal compound with some Arctic Silver 5.
Goodness gracious Wookie. Try replacing the upper case first. If that doesn't work, try the logic board. Don't waste your time with Apple. Their replacement parts are super overpriced.