"I, for one, won't be putting something that generates heat into a cupboard, it doesn't sound like a good way to extend its lifespan."
After replacing a second fried motherboard I discovered that the PC's owner was keeping it in a furniture cupboard. In use the door was only ajar enough to accommodate the cables. Apparently he didn't want passers-by in the apartment block to see he had something worth stealing.
Biting the hand that feeds IT
