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For the past few years, I have been experiencing thermal shutdowns with my Macbook. I didn’t use it for a while, but got around changing the battery and heat sink. After replacing the heat sink, the temperatures have gone down with a few degrees Celsius, but easily climb to 90+ degrees with just Chrome open. For my computer to be usable, I have to run it with Macs Fan Control at 100% fan speed, otherwise the thing just shuts down. I am a bit lost for words here and am uncertain what I have to do to fix this. Has anyone had similar experiences? In general: This happens more often on battery power than on AC power, but I never use my laptop on AC anymore;The screen just turns black, the fans speed up slightly, and the system just shuts down;If I don’t set the fan speed to 100%, the body of the laptop becomes hot instantly- even before changing the heat sink.
Did you try running the onboard diagnostics to see if can aim you to a problem? Restart your system press the D key to enter. Reference: Mac startup key combinations How much RAM does your system have as well as the size of your drive and the free space it has. You maybe just pushing your system too hard as it doesn’t have the needed RAM and as your system will leverage virtual RAM the drive may just not have the needed free space. As a rule of thumb I recommend having 1/3 of the drive empty for system using 256 or smaller drives, and for 500 or 1 TB 1/4 free. I would also use a better thermal monitoring app like TG Pro with the full version you can log your temps to see if combined with Activity Monitor you can link what process/es are pushing your system, hard. Remove Macs Fan Control fully, your system should not need it, and you are likely cooking it instead of fixing the root issue. The last issue here is your battery! I would recommend you monitor it as well using this gem of an app CoconutBattery. Your system is quite old if you haven’t replaced your battery I would do that ASAP as it also can cause issues you what you are seeing. Post a snapshot of the apps main window here for us to see Adding images to an existing question
