Two motherboards dead in a few months — need guidance (long explanation)

Posted by Left-Cow5976@reddit | buildapc | View on Reddit | 5 comments

Hi, Here’s the full story — I’ve had two motherboards die in just a few months with the same PC.

Important note: for now I’m not including component models or photos. I’d like to first hear general opinions. If needed, I can later provide exact models or upload images.

Context • PC worked over a year perfectly in another house. • In my new house for about 2 months, initially fine. • Added a second RAM stick recently (was using just 1 before).

First failure • Had an ESP32 connected to an external PSU (messy wiring). • Plugged ESP32 into PC via USB-C to flash WLED. • At that moment, PC shut off: • GPU fan stopped, monitors black. • Other fans and RGB kept running. • Case power button didn’t respond → switched off PSU. • After that, PC never turned on again. • Tried: jump motherboard (nothing), jump PSU (PSU powers on). • Concluded motherboard fried from ESP32 wiring. Bought new motherboard.

Second failure • After months of normal use (including Wake-on-LAN). • Returned from trip, PC wouldn’t start with case button (already broken). • Tried Wake-on-LAN → PC did power on. • Came back later, PC had shut off by itself and never powered on again. • Tried jumping motherboard (not precise) → nothing. • Bought external case button → still nothing. • Jumped PSU → PSU powers on.

Current situation • Two motherboards dead in a few months. • First time I could blame ESP32, but this time nothing unusual happened. • I don’t have a multimeter to check PSU voltages.

Question

What seems the most likely cause here? What would you check first before risking another motherboard?

Thanks a lot for any advice!

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changen@reddit

dirty power from the wall.

WildHoboDealer@reddit

So I have a similar issue going on, and it's an ungrounded outlet. If it were truly the wall power why would it not kill any other devices on the surge protector with it?

cause most other circuits don't need clean power.

tybuzz@reddit

It's possible you partially damaged the PSU when you fried the mobo the first time and it eventually failed completely. I would start with a new psu or RMA yours if it's under warranty.

Left-Cow5976@reddit (OP)

Thanks for the reply! I don’t think the issue comes from my home AC power — I have two other PCs running in the same room on the same outlets and they’ve never had any problems.

My main concern now is figuring out whether the PSU is really the culprit without risking another motherboard. Since I don’t have another system to test it on, what’s the safest way to confirm if the PSU is damaged or unstable before I buy a new board?