Reviving Desktop from Water Damage


Junior Member
Dec 11, 2015
Hey everyone! Long time lurker, these forums have some great technical content, but now I finally have a reason to post. No pun intended.

My desktop is next to my window, and a week ago I forgot to close the window in a thunderstorm and got water on my motherboard. I walked into my room to the sound of electrical popping and my power supply switching on and off due to the short circuit. Dried off the water on my motherboard, pulled the heatsinks and cleaned it with isopropyl alchohol, searched all the other components for signs of water, put the essential components back together, and no luck. With the CPU in, the power supply fan would just twitch when I pressed the power button. Without the CPU, it spun up for about 10s. Different RAM sticks didn't help. I tested the power supply with a jumper and multimeter, and all the voltages are fine, and it powers another computer fine.

I ordered another motherboard on ebay, and the power supply fan would spin for a couple seconds and turn off. This motherboard has an LED display for debug codes, but it didn't show anything.

Then I took everything apart and it sat on the shelf for a couple days while my internal speaker arrived. Put it back together with the speaker and the power supply no longer turns on using the power button on the motherboard. The power supply still powers up with a jumper. Measuring the voltage of the green power on pin at the power supply connector, it stays at 5V even when I press the power button. I verified with a continuity check that the power switch still works.

Wtf is going on? The computer should power up and show a debug code if it were bad RAM, so I'm pretty sure it's either CPU or motherboard again. I'm trying to find someone with an LGA1150 computer so that I can test the CPU.

Parts list:
Asrock H97M Pro4 (water damaged)
Asrock Z97 Extreme4 (second hand, owner said it worked)
Intel G3258 (questionable)
G-Skill Aegis DDR3-1600 4x4GB (questionable)
Corsair CX-430M (known good)


No Lifer
Aug 25, 2001
Honestly? I would let it dry out for two weeks, and if it doesn't power up after that:
Maybe replace the PSU with a "known good" replacement.

If that doesn't work, I'd probably just write it off as a complete loss (but save the HDD / SSD for recovery purposes).

Unless, you are willing and financially able to go down te rabbit-hole of part-swaps, with what may be "walking wounded" parts, that may kill new parts that you mix with them, until you either give up, or wholesale-replace the group of bad parts.


Junior Member
Mar 10, 2017
I worked for an onsite replace part or parts company awhile back, and learned that lesson VirtualLarry pointed out: often, in situations like or similar to thread starter's, it is best to group-replace all suspect hardware components; for example: often, I was sent out with power supply, motherboard, ram -- and would coldboot test with just a keyboard attached. If that coldboot returned the right "noise and light", I would add the other components one at a time.
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Platinum Member
Aug 17, 2006
You KNOW the keyboard was soaked and did your best to dry it. Your tale however does not include a test I would do. DISconnect your keyboard and try to turn on. If it DOES start up normally and then tells you there is no keyboard, you know that's where the problem is.