Your comment reminded me of my K6 (or was it a K7) based PC I had assembled as a high schooler of modest means.
My goto testing protocol was to recompile the Linux kernel and make GNU chess play itself at the highest settings.
I was quite disheartened to find that my rig would crash out repeatedly. Not a single successful compilation of the kernel. Then on a whim I removed the case and pointed my table fan at it. Voila, everything worked.
I had planned to get some more thermal paste and redo the thermals and put the case back. But I never did.
Then one day the dialer of my landline got fried by a thunderstorm. No problem I used to dial using my modem and my skeletonic linux box.
Great setup when the money is tight. Good times.
Table fan was the way to go in our first LAN party during the summer of the year 2000 in the south of Spain. These computer case side panels were all piled against the wall.
as a kid I once had a PC that would make a very loud siren noise when it was overheating. I don't know why they thought that was a good idea but I did solve it by pointing a fan at it. Somehow my parents never came and asked what's that noise.