I built a new mining rig, first on a Lian-Li motherboard tray, then I moved it to a small piece of plywood because I couldn't fit the third card on with the tray. Brand new $200 plus 1000W power supply. Powered it up and let it run for several hours.

I noticed the smell coming from the "mining room" was like an electronics parts factory. Clearly something was really running hot and burning off chemicals. I'm checking the components and finally check the power supply - it was so hot it was painful to the touch. I shut the rig down and started thinking I might be drawing too much power and would have to remove one of the cards.

Then I started looking at the power supply - it was sitting face down on its own fan! I was so excited to get the rig working that I made a dumb mistake that almost burned up the power supply.