dead mb

[hfl12]

Guys,
I have a question for you. Let say I have a motherboard that is completely dead. There is no sign of bad caps,burned diodes or cables. I try to remove the cmos battery, hold down power button, do bios recovery, look at bios log which shows no known problem, change different rams and mouth pad. Try everything that is possible without doing hardware soldering. I find that the power jack is good with a multimeter. Also, there is voltage on the mb. I have seen this type of problem in the past, and most of the time I replace the mb. However, I have seen motherboard manufactures and some experts bring the dead mb back to life. Alright, maybe they solder a new bios chip or some other chips? But how did they know which chip is corrupted? is there an equipment that can look for every single chip on the board for corruption? What do you do in this case? Thanks.

[Mad_Professor]

Re: dead mb

I'm guessing this is a laptop because you said power jack.

What kind of laptop is it?

[budm]

Re: dead mb

They have what its called 'bed of nails' for board testing which is ran by computer that is programmed to look at the reading from each test points on the board.
http://en.wikipedia.org/wiki/In-circuit_test

[hfl12]

Re: dead mb

I have had a couples in the past that I don't remember the name. The one most recently was the asus g73j. Another one was a desktop emachine, this one turns on but stuck at post.

[Uranium-235]

Re: dead mb

is any hard drive hooked up?

[hfl12]

Re: dead mb

Yes, but your question surprised me. In general, mb should boot up fine without anything but a processor connected to them. Maybe, there is something that I don't know?

[999999999]

Re: dead mb

It will need processor, at least one memory module and possibly that in a certain slot, "sometimes" a viable CMOS battery, and either integrated video or a video card.

What exactly does it do? Does it turn the PSU on and the fans spin or nothing? Does it generate any beep codes, or does it beep with no memory installed?

Usually when a non-manufacturer brings a board back it is because they had a strong suspicion of what the problem was from past history of board failures or subcomponent problems, otherwise people with the skills and the test equipment to do the work, are worth more in the time to do the work than the board would be worth if working again so you might say those that are successful are often just lucky and bragging when there is no evidence to go on and all the more common problems were ruled out.

[Uranium-235]

Re: dead mb

actually my implication was about the one you previously said that 'booted up but froze during post'. Sometimes bad hard drives will cause a bios freeze

[hfl12]

Re: dead mb

actually my implication was about the one you previously said that 'booted up but froze during post'. Sometimes bad hard drives will cause a bios freeze

I see. I changed everything. Memory, hd, cmos batter, psu, graphic card, everything except processor.

[hfl12]

Re: dead mb

@999999999

Good point.
Like I said, there is nothing. Completely dead- no beep code. You mentioned non-manufacturer,do you know what a manufacturer would do in this case? I guess they have a special equipment for this board?

[999999999]

Re: dead mb

^ Manufacturers have to have equipment set up to test boards when they're made, and sent in for repair. I've read a few articles over the years that showed pictures of manufacturer employees doing testing but unfortunately I don't remember where I saw them.

[hfl12]

Re: dead mb

That's cool. Thanks. I'm surprised topcat hasn't said anything.

[momaka]

Re: dead mb

Could be a Northbridge/Southbridge or GPU (if integrated) BGA issue. A reflow might bring it back. When in doubt, do a full board reflow in the oven.

[Spitz]

Re: dead mb

Guys,
I have a question for you. Let say I have a motherboard that is completely dead. There is no sign of bad caps,burned diodes or cables. I try to remove the cmos battery, hold down power button, do bios recovery, look at bios log which shows no known problem, change different rams and mouth pad. Try everything that is possible without doing hardware soldering. I find that the power jack is good with a multimeter. Also, there is voltage on the mb. I have seen this type of problem in the past, and most of the time I replace the mb. However, I have seen motherboard manufactures and some experts bring the dead mb back to life. Alright, maybe they solder a new bios chip or some other chips? But how did they know which chip is corrupted? is there an equipment that can look for every single chip on the board for corruption? What do you do in this case? Thanks.

You need a bios post board to show what is happening before the video card is started. It shows the numbers as things progress and the numbers tell how far the cpu and chipsets got. I have used them many times for desktop boards but have not had any that work on laptops. Here is what i found:

http://www.amazon.com/laptop-motherb...ef=pd_sim_pc_5

[ben7]

Re: dead mb

@999999999

Good point.
Like I said, there is nothing. Completely dead- no beep code. You mentioned non-manufacturer,do you know what a manufacturer would do in this case? I guess they have a special equipment for this board?

Has the PSU been tested and confirmed working? If it is, check to see of the power switch is working correctly.

[hfl12]

Re: dead mb

You need a bios post board to show what is happening before the video card is started. It shows the numbers as things progress and the numbers tell how far the cpu and chipsets got. I have used them many times for desktop boards but have not had any that work on laptops. Here is what i found:

http://www.amazon.com/laptop-motherb...ef=pd_sim_pc_5

thanks, I have never tried try one one of those. But I mostly work on laptops.

[hfl12]

Re: dead mb

Has the PSU been tested and confirmed working? If it is, check to see of the power switch is working correctly.

I work mostly on laptops. Sometimes, I test the connection with a multimeter on the mb.