My IIGS has been running without a hitch for the past few years. I should have known better than to have left the twenty five year old machine running unattended while going outside to do some yard work. In the half hour that I was outside the power supply had failed and produced an awful mess. The room took weeks to air out. The peripheral cards, motherboard and monitor still smell of smoke and the case now has a nice brown burn mark on top. I took the power supply apart and just stood there for a while thinking, “What a mess! Am I every going to get the urge to clean that up?”
I thought I had done well by having a spare IIGS machine which I use for testing my electronic projects. When it came to turning it on all I got was the power light flicking on and off every half second or so. Frying two power supplies in one week didn’t impress me very much. I took this power supply apart and found that a large capacitor had blown it's top. However replacing the capacitor has not fixed the problem. The same symptom still persists. More load testing needed I think.
I intend on getting the power supplies fixed but sadly my trust in old hardware will never be the same again.
Update: 7th September 2017.
During OzKfest 2017 my machine let out the magic smoke. It would have been less to clean up if someone had pulled the power cord out, instead of watching and taking photos of the power supply spark and bellow out the smoke. But then again we managed to get this great photo. Turning off the power supply in this case did not work because this older unit had the line capacitor attached across the power plug and not to the supply circuit board.