How to know if the problem is from a bad cap ?

[hary66]

Hello.

I have an MSI M670 MS-1632 laptop with strange behaviour.
(the screen sometimes goes ok, sometimes, it doesn't light on at all, sometimes it lights on then goes off, and sometimes it transform the writing in many rectangles moving the writing in different pieces all over the screen. It need 1-3 times to start. Then it goes ok for hours. Sometimes, not.

This happens during the POST or during the OS is loading or after the OS has loaded.

It made me thinking of a bad cap symptom. Because in some way, it behave like a versatile PSU with old capacitors.

But on my MOBO, the capacitors are smaller than on a normal PC and hardly reachable.
Would be good to know exactly witch one is going weak instead of replacing all of them.

By the way these caps are not easy to identify and find !

Is it possible to check the voltage on each capacitor with a scope to find the problem?

I was thinking to weld a 30cm pair of wire on each end of each capacitor, then drag the wires outside the case and check with the scope.

What do you think ?

[pc7fan]

Re: How to know if the problem is from a bad cap ?

That could be the video card or the integrated graphics doing that (squares on the screen), is starting to fail, IIRC the video memory can cause that hope it's not that :/

[mariushm]

Re: How to know if the problem is from a bad cap ?

Sounds to me like some sort of weak connection, maybe bad solder joints under the memory chips for video card, or the video card chip itself. When the laptop heats up and the solder expands a bit, you get reliable connection.

I doubt the capacitors are causing this problem, but it's not impossible.

I don't know who makes those capacitors with black strip in the first picture. They're probably electrolytic capacitors, in surface mount can. The first two that are at the bottom are 100uF ... I would guess 16v or 25v rated.
The one in the second picture is 330uF, probably 6.3v rated, or 16v rated. Measure voltage across capacitor pads/leads and if it's below 5v, it's probably 6.3v. I think that one is still electrolytic.

The ones in the third and fourth picture are polymer capacitors. The ones in the third picture are made by United Chemi Con (or Nippon Chemi Con, same thing), They're 560uF, 4v rated and I really doubt those or the ones in the fourth picture could be the problem.

My suggestion would be to get a hair dryer and slowly warm up some areas of the motherboard, like the video card chip, or the chipset and see if the issue dissapears when you try to start the laptop. If it does, you probably need to do a reballing of that chip.

[Ramee]

Re: How to know if the problem is from a bad cap ?

They called it artifacts. Change the vga chipset.

[hary66]

Re: How to know if the problem is from a bad cap ?

Thanks you for your help.

I've been reconsidering the fact and if I hit the computer (keypad) a bit, it would happen everytime.

I went underneath and hit the different chip with no success to make it fail !
Of course the GPU (NVIDIA G6100) is underneath the cooling system so not really reachable.
I try to bend the MOBO with no more success to localise the failing area !

The defect mostly response when I knock the computer, but not the MOBO

[SteveNielsen]

Re: How to know if the problem is from a bad cap ?

Try reseating and/or substituting RAM, the video RAM is shared with system RAM.

[RJARRRPCGP]

Re: How to know if the problem is from a bad cap ?

Squares=Probably the GPU.

[Clutchbox]

Re: How to know if the problem is from a bad cap ?

I don't know who makes those capacitors with black strip in the first picture. They're probably electrolytic capacitors, in surface mount can. The first two that are at the bottom are 100uF ... I would guess 16v or 25v rated.

Those black "CFK." smt lytics are Panasonic brand.

According to the datasheet:
- The first line '100' means '100 uF' (Capacitance)
- The second line 'C' means '16 Volt' (Rated Voltage)
- The 'FK' is the Series identification
- And the Black Dot (.) means Lead-Free Product
- The third line is the Lot Number

[hary66]

Re: How to know if the problem is from a bad cap ?

Try reseating and/or substituting RAM, the video RAM is shared with system RAM.

If you're talking about the DDR2 SoDimm Ram, I've already substitutd them. As I've 2 SoDimm, I've left only one at a time, them moved it to the other slot, then did the same with the 2nd RAM, but nothing better neither worst : No change !


For those interested, I've posted some more pictures to show what happens, (the video artifacts) from different try.

Also some picture of my board and the GPU and other chip.
I have a thermal camera and I noticed the chip on picture 11 (the one with NO thermal dissipater) is running at about 70°C.
I can't say about the CPU and GPU because they're overcome with the FAN/radiator, but I can see the GPU is running at quite high temperature.

The CPU has thermal paste (I cleaned the old one and put new paste), and the GPU has thermal pad that I didn't' replaced because I don't have some !

Hope this will help you to give a better idea about the problem.

[Clutchbox]

Re: How to know if the problem is from a bad cap ?

Well, i think your Nvidia G6100 Chipset is bad (Northbridge with GPU in it), unfortunately a very common problem. To summon it all up: http://www.laptoprepairwatford.co.uk/nvidia_fault.html
Also Google for more information and take a look here.

I think only replacing the NF-G6100 chip for a brand new one will fix it, but the problem is inside this 'chip-package' itself (failing connection between Chip Die and green Organic Package), so the problem could come back after a while.

[Th3_uN1Qu3]

Re: How to know if the problem is from a bad cap ?

The correct action is replacing the G6100 with one manufactured 2010 or newer. The problem will not come back (at least before the hardware is obsolete).

[hary66]

Re: How to know if the problem is from a bad cap ?

Well, i think your Nvidia G6100 Chipset is bad (Northbridge with GPU in it), unfortunately a very common problem. To summon it all up: http://www.laptoprepairwatford.co.uk/nvidia_fault.html
Also Google for more information and take a look here.

I think only replacing the NF-G6100 chip for a brand new one will fix it, but the problem is inside this 'chip-package' itself (failing connection between Chip Die and green Organic Package), so the problem could come back after a while.

Very disappointing indeed ! My laptop is from 2006, so 8 years old.
Would it be worth it attempting a new chip and a reballing ?


Edit :
I think that's what I need so !:
http://www.diskdepot.co.uk/acatalog/...g6100-n-a2.htm

The correct action is replacing the G6100 with one manufactured 2010 or newer. The problem will not come back (at least before the hardware is obsolete).

Do you think it's possible to find a new chip already with the balls ?
So I have only to drop i and heat it in place. I don't have the stencil and equipment to prepare it and this equipment is quite expensive for only one time use !

[Th3_uN1Qu3]

Re: How to know if the problem is from a bad cap ?

All new chips come pre-balled. However, this is not something you're going to manage with just a hot air station or heat gun. It can be done with a hot air station but you need a special BGA nozzle (around $20 from China), one or two multimeters with temperature probe, and some sort of a preheater. Without a preheater you're definitely going to damage the board.

I do this kind of work on a weekly basis at least, and the equipment i use would make some people laugh. However, i have great results. BGA reworking is more about the materials (flux, solder wick and so on) that you use, than what you use to solder the chip to the board. As long as the heat is reasonably even it's going to work. You do need quite a bit of practice though before you start getting it right.

[hary66]

Re: How to know if the problem is from a bad cap ?

All new chips come pre-balled. However, this is not something you're going to manage with just a hot air station or heat gun. It can be done with a hot air station but you need a special BGA nozzle (around $20 from China), one or two multimeters with temperature probe, and some sort of a preheater. Without a preheater you're definitely going to damage the board.

I do this kind of work on a weekly basis at least, and the equipment i use would make some people laugh. However, i have great results. BGA reworking is more about the materials (flux, solder wick and so on) that you use, than what you use to solder the chip to the board. As long as the heat is reasonably even it's going to work. You do need quite a bit of practice though before you start getting it right.

Thanks very much for your advices !

I found these, but some specify the date 2010+ or 2009+, and with or whitout balls.

http://www.ebay.fr/itm/HOT-New-Nvidi...item27e0a5b85a

http://www.ebay.fr/itm/HOT-2010-Bran...item2a399687ca

a second hand one from 2005 ????
http://www.ebay.fr/itm/1PCS-NVIDIA-N...item566149f48f


One after 2009 new with balls :
http://www.ebay.fr/itm/1-Piece-New-N...item5d349c338a

Witch one would you go for ?

I have at least 1 temperature probe meter, I can borrow a 2nd one.
For the preheat, I can put it on an electric radiator or Do you have better option ?

What else do I need and what kind of flux etc ...

It would be a first time but it's a good opportunity anyway !

Would you have some good link explaining the DIY way of doing it.

[Th3_uN1Qu3]

Re: How to know if the problem is from a bad cap ?

The 2009 or 2010 are the ones to use for a long-term repair.

[hary66]

Re: How to know if the problem is from a bad cap ?

Hi I'm coming back enquiring an idea.

Would it be possible to neutralise the NVIDIA chipset and add an external Graphic Card on my laptop to be sure the problem is from the NVIDIA G6100 chipset.

I have IEEE1394 port (firewire) and ExpressCard slot free on the laptop. Would one of these would be useful.

Sorry for insisting working on this old laptop, but I hate not to be sure and not understanding about what I'm doing.

I think it would need to neutralise integrated NVIDIA chipet in the BIOS, but I'm not sur this option is available ? Were can I finf it ?

And what would happen if I neutralise the integrated NVIDIA chipet in the BIOS and the new external video card doesn't work or is not detected ? I would have no way to see back anything on the screen ?

[Th3_uN1Qu3]

Re: How to know if the problem is from a bad cap ?

No you cannot do that. Some laptops do have the option of using an external video card when used with a docking station, but yours does not.

Either way, it is 100% the nvidia chipset at heart of this problem, it is a common issue. So common in fact, there has been a lawsuit somewhere in 2009 IIRC, where nvidia lost a significant amount of money and was required to pay for repairs for most of the affected laptops. Most laptop makers extended the warranties for these laptops.

[hary66]

Re: How to know if the problem is from a bad cap ?

Ok, I see, that's the reason I couldn't find a way in the BIOS to switch from integrated chipset to an eGPU.

I saw the story about the lawsuit, but we are now in 2014, almost 2015.
By the way, very interesting. They kept on saling they're bad chipset for so long !

I think it would be hard to ask about an extended warranty to get a fix or refund !
A shame because that's my brother's laptop and it failed moreless in 2009 actually. But he and I didn't know at that time !

I had a look about G6100 NVIDIA chipset issue on MSI M670 but didn't find any other people with the same problem on this particular laptop.

Plus I'm in France and we don't have class action here. I doubt a guy on its own would go to court for such a problem here !

Any idea I could get a refund ? It was almost 650€ in November 2006 !
Would it be worth it to get a try ?

Plus now I opened it and the "warranty sticker" is gone !

Thanks so much for your help and advices, indeed. I really appreciated.

I might attempt a DIY replacement of the chipset. It would be a good opportunity to learn something.

[Th3_uN1Qu3]

Re: How to know if the problem is from a bad cap ?

A DIY replacement is definitely possible. The 6100 is a small chipset and it's not too much trouble to replace.

But first you will need to get some experience if you decide to build your own rework station. An alternative would be just giving it a good reflow and then undervolting its power supply. This will give you around 6 months to 1 year of life from that chipset. Just reflowing without reducing the operating voltage will last between 1-4 months, depending on your luck and the laptop's workload.

[hary66]

Re: How to know if the problem is from a bad cap ?

No you cannot do that. Some laptops do have the option of using an external video card when used with a docking station, but yours does not.

First I'd like to know how you know it ? Where did you get this information from ? Sorry to be so curious.

But first you will need to get some experience if you decide to build your own rework station. An alternative would be just giving it a good reflow and then undervolting its power supply. This will give you around 6 months to 1 year of life from that chipset. Just reflowing without reducing the operating voltage will last between 1-4 months, depending on your luck and the laptop's workload.

"Reflow" , you mean giving the chip a heat shoot without replacing?
Undervolting ? How ? I haven't seen such option in my BIOS !

can I use my regulated hot air gun for top, and a well regulated (PID Arduino stuff) grill underneath for preheating ?
Would you have some good tutorial link for DIYers.

Well, i think your Nvidia G6100 Chipset is bad (Northbridge with GPU in it), unfortunately a very common problem. To summon it all up: http://www.laptoprepairwatford.co.uk/nvidia_fault.html
Also Google for more information and take a look here.

I think only replacing the NF-G6100 chip for a brand new one will fix it, but the problem is inside this 'chip-package' itself (failing connection between Chip Die and green Organic Package), so the problem could come back after a while.

Would a reflow work for such a problem ?