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Bakaka BakakaFlag for Ghana

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Laptop wont boot up?

Hi,

I have a problem with my Toshiba Laptop (c850), the power adapter, of the laptop itself blew up when i connected it to the laptop. The smoke came out of the power adapter and it fries now so i went and source another same power adapter from the local shop but when i connect it to pwer the laptop on, the laptop wont come on.

I am suspecting, the motherboard of the laptop has fried too or could be the power tip burnt.

I am going to repair the laptop but i want to ask whether the simple fix is to purchase a OEM motherboard is ideal or solder the power tip.

Another question is, if i were to purchase a new motherboard, will the cpu come with it or i have to purchase the cpu separately?

I would like to seek some other suggestions before i make the final decision.
Regards,
B
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John
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I am going to repair the laptop but i want to ask whether the simple fix is to purchase a OEM motherboard is ideal or solder the power tip

Based on your description, you have damaged the input section of the motherboard or even more. Soldering the power tip (I am not sure what that means exactly) will not do anything positive.

Ask the repair shop for an estimate and decide whether the repair is worth it.
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Dr. Klahn

The fact that the power supply did not fail until it was connected to the laptop suggests that the problem was in the laptop, not in the power supply.  Switching power supplies try to fail-safe but if the switching MOSFETs short, the entire voltage of the output section's filter capacitors can (very briefly) appear across the output.

This suggests that the motherboard was the original problem, which then destroyed the original power supply. Since the problem in the motherboard remained, that may have blown the protective fuse in the new power supply as well.

You should check the voltage at the tip of the new power supply's output cable to see if the supply is (a) still working and (b) within the expected voltage range.

Then you can consider whether it is worth replacing the motherboard.  Laptop motherboards are often sold with the processors still attached as there is not a large market for "naked" laptop CPUs.  fleabay is a good source for replacement motherboards and that will give you an idea of what you'll need to invest to recommission the system.
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ASKER

Thanks,

@DrKlahn - the new power adapter is fine and it is not affected.

I tested the voltage with my meter-tester and the voltage was able to show 19v on my tester.

Moving on - I have attached photos of the laptop.

Will this means that the motherboard is gone or the dc jack needs replacement?
screen-1.jpg
screen-2.jpg
You can try replacing the jack, but in my experience jacks go "open", they do not normally short out. Most likely your motherboard caused the issue.
I would try replacing the power jack inside the laptop first.  It is fairly cheap part and easy to replace since you already have the laptop apart.
And if the laptop still not powering up (once the dc jack has been replaced with the new one)?

what would be the next step?
Replace the motherboard (new jack and you say the adapter is fine).
ok will do that. thanks all.
I agree the motherboard.
might as well get the motherboard then if this is the case. how would this kind of problem indicates where the fault is:

(1) will it be the motherboard?

(2) or the DC Jack inside the laptop?
You said you got sparks and smoke. That is not likely the jack (not likely), but rather a failed motherboard. Nothing is absolutely certain, of course.
the sparks was coming out from the previous power adapter and that is why i went a buy a new power adapter.

so i take the problem lies in the Motherboard then which needs a new replacement.
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John
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Thanks, John - ill go ahead then and buy a new Motherboard for this laptop.
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Thanks,

there is no debris nor damage to the internal power jack - upon checking.

Ill start by getting a new power jack (internal to the laptop) first and if the laptop still wont boot up nor power up then ill take the motherboard as the source of the problem.

I think it make sense now.
Thanks
buy a new laptop it will be cheaper, of if under warranty return for replacement.
Oven when you see smoke or see sparks fly you will get a smell as well, often if things like capacitors or transistors short out you will get a burning smell. Try to see if there you smell a burning smell on the board, that would give you a good indication that the board was shorting out. It could have been a bad powersupply that shorted itself out and also shorted out the mobo.  Like other people mentioned it is probably cheaper just to buy a new laptop and transfer the data from the old hard drive to the new laptop. If the laptop was under warranty this would have been considered a safety capture and the manufacturer would have to replace both the mobo and the powersupply.  Was any liquid spilled on the laptop? As this could have shorted out the system if it was not fully dry when it was plugged back in.
@web_tracker - thanks for your comment. There is no spilled on the laptop. my next fix is to purchase a dc jack (internal to the laptop) and if the laptop itself still does not boot up then i know for sure the motherboard is where to take from.

so that is where i will be heading to.
did you check the motherboard yet for burn marks?