How much was it to get high end thermo paste?
Unless you intend to void your warranty, you should not take the machine apart to do this yourself. If you choose to repair at a shop, make sure to ask them to show you proof that they are an Apple Authorized Service Provider
and the employee is an Apple Certified Repair Technician
. If they cannot provide proof ask them to log in to GSX while you watch. If they are unable to do so, take your machine elsewhere.
Preferrably, if you're near an Apple Store, you should take the machine there and have them inspect it. You may find lots of hidden dust clots that are choking the machine to death and causing overheating. Thermal paste is not that often the culprit in modern Apple products (it was years ago, but Apple updatd its guidelines on how much to use and how to apply it).
Whatever you do, make sure you've got yourself covered when getting any repair done on your machine. Apple won't cover improper or unauthorized repairs.
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