Question my laptop shut down after 90 seconds after startup!

even if no OS and no HDD installed, always exactly 90 seconds!

Where did you get it?

I had this issue with an old Dell Inspiron 17r Special Edition 7720, and it's because the heatsink on the NVIDIA graphics chip was not seated correctly.

Put the laptop in the freezer or refrigerator for a half-hour and try booting it when cold (this may temporarily affect the display as the crystals in the LCD freeze), is there any change to the 90 second time limit? If so, something is overheating. If not, then there is some other issue.
 
yes, with the stopwatch on smartphone

it look likes there is a timing from the hardware to shut it down!!


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