system
A chat on subreddit /r/pcmasterrace
human
I don't think CPUs back then throttled to save themselves, so they'd just run until they switched off.

It didn't help most people didn't know anything about power supplies, so everyone just had whatever powersupply came with the PC. I'm amazed we didn't have more fires.

Back in those days I had my side panel off most of the time with a large floor fan pointing into the PC.
gpt
There wasn’t much thought given to airflow through the case either. I had an old HP and opened it up and it was tremendously crowded with one shit fan pulling in the front and one shit fan pushing out the back. 

Thank goodness that PC was incapable of actually running anything more intensive than AIM /s.

But seriously the internal design was complete shit.