No explanation for dead mobo...

[Claudius-07]

What are the odds! So I’ve had my trusty i7 870 cpu running in a Gigabyte HM55-USB3 LGA 1156 for as far as I can remember, pretty much from the day that cpu was released. It has been FLAWLESS. Runs so cool, not oc’ed, had a Corsair H70. It’s just been the damn best computer (reliability wise), I’ve ever had.
Like an idiot I decided it was time to open it up and clean it up a bit. Also I did not want to work on it my office in the basement so I unplugged everything, brought the case and stuff upstairs where I could work on it on the living room table, lots of light. I did not even begin to open the case up to start cleaning, just decided to hook everything up back up, connect to the monitor on the living room table and turn the computer on, and nothing. No beep, no post, nothing. Folks I have tried everything. I reset CMOS.. pulled battery out, changed Power Supply, pulled out video card, tried a different card, pulled out RAM, tried different ram, less ram, more RAM, unplugged all hardrives. NOTHING. On the board there is this little light which would always be on. Nothing. How is this possible? There is no carpet in my house, just hardwood. As I carried it up the stairs from the basement, I was careful, there is no rhyme or reason for this. It is dead dead dead. The video card and hardrives and RAM are all fine as I have moved them to a different system to test. So at this point it’s either the CPU or motherboard but I assume it’s the motherboard.
Can motherboards just DIE like this? Now good luck in trying to find a replacement 1156 board. God there isn’t a place that carries them anymore.

 

[SolderingNoob]

What are the odds! So I’ve had my trusty i7 870 cpu running in a Gigabyte HM55-USB3 LGA 1156 for as far as I can remember, pretty much from the day that cpu was released. It has been FLAWLESS. Runs so cool, not oc’ed, had a Corsair H70. It’s just been the damn best computer (reliability wise), I’ve ever had.
Like an idiot I decided it was time to open it up and clean it up a bit. Also I did not want to work on it my office in the basement so I unplugged everything, brought the case and stuff upstairs where I could work on it on the living room table, lots of light. I did not even begin to open the case up to start cleaning, just decided to hook everything up back up, connect to the monitor on the living room table and turn the computer on, and nothing. No beep, no post, nothing. Folks I have tried everything. I reset CMOS.. pulled battery out, changed Power Supply, pulled out video card, tried a different card, pulled out RAM, tried different ram, less ram, more RAM, unplugged all hardrives. NOTHING. On the board there is this little light which would always be on. Nothing. How is this possible? There is no carpet in my house, just hardwood. As I carried it up the stairs from the basement, I was careful, there is no rhyme or reason for this. It is dead dead dead. The video card and hardrives and RAM are all fine as I have moved them to a different system to test. So at this point it’s either the CPU or motherboard but I assume it’s the motherboard.
Can motherboards just DIE like this? Now good luck in trying to find a replacement 1156 board. God there isn’t a place that carries them anymore.

I am shocked by that (no pun intended). I'm still very much a noob to the whole PCB thing but if I were you I'd take a multimeter with fine probes and begin testing to see where the board might not have any power. I did this recently with a dead mobile phone PCB. It was getting power everywhere that I checked, but I didn't check every possible connection...there are so many.

One trick you can try is to reflow the board. If you feel like you have nothing else to lose, reflow it in your oven. There are youtube videos that show people reflowing xbox 360 boards in their ovens at 390 degrees. I recently did it with some random board I found in my supplies at 390 F it didn't melt any of the thermosetting plastic components so I felt good about that.

That's what I'd recommend--test for 0 volts with a multimeter all over the board, and/or reflow it. You have nothing to lose at this point I think.

Perhaps someone else who has more experience with dead boards can pitch in a more helpful response.

 

[BigChickenJim]

I have four theories for why this happened.

1. You blew up your PSU (and by extension your mobo if the PSU didn't have a failsafe) when you unplugged/replugged your comp. It's rare, but I've heard stories of PSUs being scorched by electrical mini-surges when people forget to flip the I/O switch off during unplug/replug. I know you tested a different PSU, but if the surge made it to the board that test would be moot.

2. The board got tweaked as you moved it. How is the board oriented in the case? Is there heavy stuff hanging off of it (I'm not familiar with the H70's weight on the mobo)? If so, it could have caused enough flex to break a circuit if you were a little rough or if the case was jostled/held at an odd angle.

3. You have a dead wall outlet upstairs. That seems too easy, but Occam's Razor is a mean daddy.

4. This one is a real longshot from a guy that's never used a water cooler (so it's likely totally wrong): the cooler or pump could have leaked during the move. Or maybe you disturbed a little condensation and it dripped.

It wasn't static if you never opened the case. Very weird.

 

[CA19100]

3. You have a dead wall outlet upstairs. That seems too easy, but Occam's Razor is a mean daddy.

That's my theory too. OP, have you tried plugging something else into that outlet to test it?

 

[Claudius-07]

Thanks for all the help folks. It was not the wall plug, as I actually tried a different one and tried plugging somethign else into that. But I hear yah, sometimes it's the darnest thing LOL.
Well I took the mobo, cpu, watercooler and RAM and brought it downstairs and put into this testbed I made. Again no power. heck nothing. I finally decided to remove the H70 and look at the cpu and I have NO IDEA how this happened but there was water in there so i guess the H70 leaked and buzzed everything up. So lesson learned. NEVER move or open your computer . Thanks guys.

 

[BigChickenJim]

Wow. That theory about the water cooler leaking was just a shot in the dark. I am now officially scared off of using water cooling. Yikes. Sorry, man.

Opening a computer for cleaning is a necessary evil if you want to keep your hardware running for as long as possible. I clean my comp out once every 2-3 months and I clean the dust filters once a month. Don't let this incident scare you away from proper maintenance, but DO be extra careful if you use water cooling again.