Badcaps.net Forum
Go Back   Badcaps Forums > Troubleshooting Hardware & Devices and Electronics Theory > Troubleshooting Desktop Motherboards, Graphics Cards, and PC Peripherals
Register FAQ Calendar Search Today's Posts Mark Forums Read

 
Thread Tools Display Modes
Old 10-05-2020, 05:28 PM   #1
goodpsusearch
Badcaps Veteran
 
Join Date: Oct 2009
City & State: Thessaloniki, Greece
My Country: Greece
Line Voltage: 230VAC 50Hz
I'm a: Knowledge Seeker
Posts: 2,137
Angry Dangerous chinese power strip kills motherboard, is it fixable?

Hello.

Some time ago, we had an issue at the company that I work for.

Someone tried to move his stuff to a nearby desk and upon reconnecting power strip to mains there was a loud noise and some sparks.

Then the power breaker tripped.

Upon investigation, found that the ground wire was cut inside the power strip, so all the devices were running non grounded all this time and then, when the employee tried to move his computer, the floating ground wire came in contact with Live.

The following parts were dead after this:

1x Dell 24" Full HD monitor (that's where the flames came from)

1x expensive mechanical keyboard

and the motherboard of the computer got a hole on its HDMI IC.

The motherboard is Gigabyte GA-B85M-HD3 Rev 1.1

https://www.badcaps.net/forum/attach...1&d=1601940425

The HDMI IC with the hole in the center is PTN3360DBS.

https://www.badcaps.net/forum/attach...1&d=1601940425

The IC has been succesfully removed but motherboard still not working.

When connecting psu to mains, fan tries to spin then stops then retries then stops again, then gives up.

I checked with multimeter and found that it appears that 3.3V is shorted to ground and same goes for 12V.

On the contrary, checked 5V, 5Vsb and -12V and they seem to be ok.

My experience in troubleshooting mbs at this level is limited.

Do you think mobo is a goner?

Should I try to remove other components that might be shorted, hoping that at some point the mb wont appear shorted anymore and then I will have been able to spot what causes the short?
Attached Images
File Type: jpg 1.jpg (763.1 KB, 52 views)
File Type: jpg 2.jpg (493.2 KB, 44 views)

Last edited by goodpsusearch; 10-05-2020 at 05:35 PM..
goodpsusearch is offline   Reply With Quote
Old 10-05-2020, 05:41 PM   #2
goodpsusearch
Badcaps Veteran
 
Join Date: Oct 2009
City & State: Thessaloniki, Greece
My Country: Greece
Line Voltage: 230VAC 50Hz
I'm a: Knowledge Seeker
Posts: 2,137
Default Re: Dangerous chinese power strip kills motherboard, is it fixable?

Additional info:

Psu survived (Corsair VS450 CWT version)
SSD survived (Samsung EVO Sata)
RAM tested on different computer and working
CPU tested on different mb and working

Also, would like to mention that the measurements I took with multimeter and found 3.3V and 12V rails shorted to ground, were done with CPU removed.

Last edited by goodpsusearch; 10-05-2020 at 05:42 PM..
goodpsusearch is offline   Reply With Quote
Old 10-05-2020, 09:47 PM   #3
eccerr0r
Solder Sloth
 
eccerr0r's Avatar
 
Join Date: Nov 2012
City & State: CO
My Country: USA
Line Voltage: 120VAC 60Hz
I'm a: Hobbyist Tech
Posts: 7,200
Default Re: Dangerous chinese power strip kills motherboard, is it fixable?

uh no.

Unless it passed a surge or the power supply was garbage to begin with, a power strip won't kill computers.

The former, the surge/lightning was ultimately responsible, and the latter, the power supply is responsible.
eccerr0r is offline   Reply With Quote
Old 10-12-2020, 07:04 AM   #4
6BW6
Member
 
Join Date: Jan 2015
City & State: Nr. Manchester UK
My Country: UK
I'm a: Knowledge Seeker
Posts: 50
Default Re: Dangerous chinese power strip kills motherboard, is it fixable?

I had a computer that kept crashing.... nope, not virus nor malware nor the computer but a BT phone charger - made in China, this did fool me, you go fearing and looking for the obvious.

This only came to light when I noted the racket on a portable FM radio. I sawed the charger open, mains AC in to a fuse into a bridge rectifier, out came 340V DC appx. (ac input voltage x 1.414 = dc out), this went to a 4.7uF 500V capacitor a tiny RF choke, about the size of a 0.125 W resistor.... 2 or 3mm diam. would they be? Then into a 2.2uF 500V capacitor - that's it all the filtering there was, all hell broke loose when one leg of the 4.7uF capacitor became a dry joint with cracked soldering - cold joint in the trade.

The time I wasted.... the computer never crashed after I 'pulled' it. Thanks BT for making such crap under YOUR license. These things supposed to have standard of quality - damned BT what a cheap skate company.

Dave.
6BW6 is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump



Badcaps.net Technical Forums 2003 - 2022
Powered by vBulletin ®
Copyright ©2000 - 2022, Jelsoft Enterprises Ltd.
All times are GMT -6. The time now is 06:36 AM.
Did you find this forum helpful?