Your use of canned air to the vents on a regular schedule. If never done, start and hope you can avoid a deep cleaning.
My laptop suddenly turn into black screen after 20 minutes turned on. But this only starting to happen since yesterday. The laptop still running but the screen turns black and any running softwares stop. I wait for hours but nothing changes, the only way to use the laptop is to turn off the laptop or cut the power supply. But after that the laptop turns black screen within 5 minutes. I don't install anything for the last days. I need to turn it off for a few hours then it will back to 20 minutes. I format the laptop with new Windows but black screen is still the problem.
Laptop: Acer Aspire e15 e5 551g, 8gb ram (6.25 usable), Windows 10 pro x64.

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