Laptop with black screen --> fried motherboard?

phil25

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Sep 10, 2013
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Hi!
I've got a problem with my old laptop.

The model is: Toshiba A100-025
Components:
- CPU: Intel Core Duo T5500 (1,66 GHz, Cache 2 MB, FSB 667 MHz)
- RAM: 1024MB DDR2
- GPU: Chipset Mobile Intel 945GM, fino a 128 MB di RAM DDR2
- GRAPHIC CARD: Nvidia GeForce Go 7300 256 Mb Turbo Cache

The problem is that it turns on, also the status led, but the screen remains black! I've tried to connect it to an external screen and it's the same!

My question is that: could the problem be only the graphic card??? Or in these cases it's always a problem with the motherboard???

Thanks :)
 
It's probably the graphics chip. NVidia had a big problem with their chips for laptops a while ago, even to the point of a class action.

The problem lies in the chip itself and the solder between the layers. Sometimes a reflow with a proper reflow machine can bring some life back to it, or replacing the GPU by soldering the one off and soldering a new one down with a reflow machine, but the replacement chips are still flawed. You would get a few more years probably out of it, but the cost for getting a new chip and someone to put it in is usually half the cost of a new laptop and at that point, get something newer.

I have a dell that has a 7600 geforce go that went on me and I reflowed it, boosted cooling and been going strong for the last 1+ years, but I also own a $2000 reflow machine so it didn't cost me anything, otherwise, I probably would have binned it.
 

phil25

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Sep 10, 2013
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It happened many months ago... and the smell disappear!! ehehe

I'm just curious to know what are the causes of a fried computer! It's an old laptop!
In my opinion if the motherboard is fried the laptop wouldn't turn on!!
The strange fact is that the bios screen doesn't appear!

Any suggestions?? :)
 

phil25

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Sep 10, 2013
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Actually I've already disassembled my laptop! And I've searched for a replacement for the Nvidia GF go 7300 and I've found many on ebay! But as I saw on youtube replacing the GPU doesn't need soldering! there's just glue... isn't it???
 
It's the graphics chip. The laptop will boot up, but not video, hence no BIOS screen and no external display.

Even if that model isn't part of the class action, it's still 99% the graphics chip and the lead-free soldering holding the chip down to the board. Its the same reason the 360 has the red ring of death, no video, and errors and the PS3 suffers the yellow light of death, no video, booting and freezing, etc.

Current lead-free solder used, at least in older laptops, 360's, cell phones, ps3's, can't handle the heat put out by the chips over a long period of time and the solder starts to break down. The reason I have a $2000 reflow machine is that I have fixed well over 1500 360's and PS3's and laptops from the problem.
 


No, that red epoxy is just the outside of the chip that holds it in place. The actual chip is soldered down by the array of solder balls shown in the pic below. You need an infrared or hot air machine to heat up the current chip to about 230 to liquidfy the solder and remove it, then you need to clean the board of all solder, then heat the new chip in the EXACT location to about 230 for 30 seconds to get the solder to melt and stick to the pads. Every single one of those solder balls has to reattach. I've put new chips on 360's and PS3's and even a few laptops. Not for the faint hearted. I probably screwed up a dozen 360's before I got it down.

1579.jpg
 

phil25

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Sep 10, 2013
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No, that red epoxy is just the outside of the chip that holds it in place. The actual chip is soldered down by the array of solder balls shown in the pic below. You need an infrared or hot air machine to heat up the current chip to about 230 to liquidfy the solder and remove it, then you need to clean the board of all solder, then heat the new chip in the EXACT location to about 230 for 30 seconds to get the solder to melt and stick to the pads. Every single one of those solder balls has to reattach. I've put new chips on 360's and PS3's and even a few laptops. Not for the faint hearted. I probably screwed up a dozen 360's before I got it down.

Ok, so in other words... If i find the same chipset, I've to heat up the old one, extract it and replace wih the same method with new chipset! It seems easy! But with "infrared or hot air machine" what do you mean? Can I use a hair drier??

When it cools again, the solder balls will hopefully be touching the board again and the GPU will work. It needs to be the perfect temp. If it is too cool, it won't do anything. If it is too hot, the GPU itself will be destroyed.

This is tricky!! But I've to replace also the paste / liquid state solders ???
 



No, you can't use a hair dryer. It's a very precise process. Lead-free solder used in electronics usually melts at 230 degrees. 227 and you put the chip up, it rips all the traces off the motherboard. 233 and you can fry the chip or cause it to delaminate. There is very little room for error. You need a proper machine, proper flux, a good iron to clean the board, the iron can't be too hot or you'll lift the traces. This is not a DIY job, period.

This has nothing to do with thermal paste. Look at the picture I posted. Every single one of those solder balls has to be melted, from the top and bottom at the precise temp to melt it to the board. A hair dryer will not work. A paint gun will not work. I didn't buy a $2000 reflow machine because I could use a $8 hair dryer. It's because you need the right tools for the right job and the experience to do it.
 

phil25

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Sep 10, 2013
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The GPU is still good, most likely, you just need to re-shape the solder balls so that they are connected to the board again.

How do you know the GPU is still good??
I've just to find someone with a reflow machine and try to reinstall or replace the GPU!
...Or maybe just find a new/used graphic card... What's the name of the connector of the laptop graphic card? Can I replace it with other models instead of the GF go 7300, just like in a normal desktop pc ???

 

phil25

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Sep 10, 2013
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I didn't buy a $2000 reflow machine because I could use a $8 hair dryer. It's because you need the right tools for the right job and the experience to do it.

You're right, this isn't a DIY job. It's necessary a good experience and good electronic tools!!
 



It's not a card, it's a chip like the one I posted above.
 
Ah, you got lucky and got one with an actual card. Those were pretty rare back in the day, and still are. 99% of laptop GPU's are soldered right on.

Then it's a gamble if you want to spend the money and try replacing that card. I wouldn't try upgrading as the laptop BIOS might not recognize another model, but replacing with the same one if it's a card like that might fix you up.

Still a toss up if it's that, but 99% of the time when the laptop boots up, all the lights come on, but there is no video from internal or external, it's the graphics chip.
 

phil25

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Sep 10, 2013
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Ah, you got lucky and got one with an actual card. Those were pretty rare back in the day, and still are. 99% of laptop GPU's are soldered right on.

Then it's a gamble if you want to spend the money and try replacing that card. I wouldn't try upgrading as the laptop BIOS might not recognize another model, but replacing with the same one if it's a card like that might fix you up.

Still a toss up if it's that, but 99% of the time when the laptop boots up, all the lights come on, but there is no video from internal or external, it's the graphics chip.

Cool!! I'll probably buy a new one! I hope it will be cheap... :p

Thanks you very much guys!! You're the best!