Thanks for that link, Marian. I read the full thing and found it informative
My oldest computer is now more than 20 years old - is used most days - and is, and has always been, turned off when not in use.
My middle computer is now more than 14 years old - and the same goes for it as for the oldest
And my newest computer is 4 or 5 years old (I think, would need to check) - and the same goes for that, too.
I have plenty of fans of all types - and heat sinks - fitted to all three.
I have a UPS to which all three are linked AND I have air con in that immediate area.
In view of the excellent service I get from all three machines, I am happy to continue my regime of them being switched off when not in use