In article , mistermaniac
wrote:

An friend just contacted me about his old (But RETRO!!) Commodore
64which emitted a lot of smoke when he turned it on. I got a picture ofthe
mainboard, which in my opinon not much good, looks like moisture,but i am
not sure. Who can give an correct answer?

MisterManiac-

Back when they were new, the power module had the reputation that the
regulator transistors were held against their heat sink by the epoxy
potting. After some use, they separated from the heat sink, causing
either a failure or a thermal shut-down.

I never had that problem, perhaps because mine was a newer unit. However
some people became quite good at rebuilding the power modules.

Fred