Dollars to donuts that it's heat related. Heat has probably weakened some part on it. Keyboard may just have dirt or crumbs in it, give it a good upside down shaking, or vacuum it, or none of that exist there, use a straw and blow. When it fails to boot does it power off, or just freeze while fan on cpu continues to blow?
If you replace the laptop, get something low power that can take a hot climate.
Hi;
Got a friend's laptop that's 3-4 years old with Win 7. First the keyboard stopped working. Then apparently weird things started happening to it (I asked, suspecting the MB). Then it now won't boot. It tries, but doesn't succeed. Cannot boot in safety mode either. Reads the USB ports but cannot boot a bootable thumb drive. Cannot boot from DVD either. Changed the BIOS to accommodate those before the HD. Pulled the HD and still can't boot from other media. In a remote area of India (a jungle), hard to get to town to buy stuff, test, etc. But from what I know of computers, sure sounds like the MB to me. Your thoughts or ideas?
TIA,
John

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