Your machine is overheating and tripping the safety shut off.
First thing to do is to open it up and blow out the fan. Then remove the fan and clean the vent.
Next, it is probably due for new thermal paste to help transfer heat. This machine is 9 years old and some of the pastes can dry out and cease to function well.
Here's how to apply thermal paste: How to Apply Thermal Paste And the paste: crwdns2937315:0IF179-010crwdne2937315:0
Here's a video on how to clean your fan: https://www.youtube.com/watch?v=9TZLpQgb...
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