I've managed to breath life into an old HP laptop by putting it in the oven (for my father in law).
It worked for a few more months but eventually became more trouble than it was worth.
The only purpose for doing it was that he, against my better judgement, had free upgraded it to win 10.
To extract an address book from win 10 (it stores them in a different method to previous versions) is a pain otherwise - even removing the drive and reading it with a linux distribution did not work.
May have been my lack of knowledge but I suspect not.
That aside, if the fan does not come on I would initially be thinking of a power failure of some kind.