Thanks for that, Avtrician. I've been toying with the idea of checking that, even since before this problem appeared. I've even looked up the instructions for doing it. The temperature check (see post 7, above) suggests that it's not an issue at the moment though so I've shifted the job down my priority list a bit.
The absence of carpets and other warming soft furnishings here on the island, due to the climate, means that there's much less dust and fluff than there would be if the computer's kennel were further North. Lifelong no-smoking means that the sticky stuff doesn't collect on the fan and ducting either. Thanks, though. That job is on my watch list if I don't get anywhere.
Last edited by Cameronian; 13th Sep 2015 at 16:10.