Not exactly a wafer but once I tried to create a very powerful LED bulb by combining LEDs of multiple 10W LED bulbs close together and yep, it got very hard to cool it down. I wasn't expecting to get that hot but later once I gave it some thought, I said silly me of course it would be hard to cool it down. When you put together multiple elements that heat-up, the radiator-to-heater ratio quickly deteriorates.
And now when I've red the title, the heat was the first thing that came to my mind.
And now when I've red the title, the heat was the first thing that came to my mind.