Bzzzzzzzzzzzzzz humm owww

Well that’s another mystery solved. My laptop has been giving me little electric shocks for ages whenever I touched the case or screws. It seemed to be getting worse, to the extent that yesterday I sat with it on my lap, my wife prodded me and I could feel the current buzzing through me to her. It appeared I was conducting 16V mains — or thereabouts.

Being the suspicious type, I was quick to blame the replacement power pack from China which also gives shocks if you touch the connector when it’s plugged in. But with my engineering hat on I knew there had to be another explanation.

So this morning I decided enough was enough and spent ages unscrewing the twenty-five screws (of ten different types) that adorned the case, meticulously arranging them in a virtual map of the holes they came out of so I could screw it all back together with confidence. I banned the cats from the room too, as they have the uncanny ability to jump up to investigate such delicate operations.

Turns out, the last time I put the laptop back together I was less meticulous and had put some of the screws back in the wrong places, and missed one. Luckily I had kept the leftover screw in a little box, because I’m like that. When I reunited it with its brothers and rearranged the virtual map to where I thought the correct screws should go I noticed one little gap that had been missing a screw for the past fifteen months.

Right above the power connector.

All hail the Earth screw!