I have a pretty old laptop: Fujitsu Siemens Amilo Li1718. Last year I have cleaned the parts inside the case, there was a lot of dust. Laptop had started to work a lot quieter and it was a lot cooler.
Last 2-3 months it is almost all the time spinning the fan at full speed. It is hotter than it was after cleaning but.. I have opened the case during normal work and .. I just started to touching some parts trying not to short any circuitry. And you know what? I have discovered that the CPU, GPU, heat pipe and other parts are just pretty warm, but.. WiFi card is just burning. I can't keep the outer side of my hand/finger longer than a second one the thin metal cover of the card. Why would the WiFi card got so hot? I suppose it has a lost smaller wattage than CPU / GPU..