Bake laptop motherboard to re-flow solder

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Known as the oven trick [last resort] for certain model line HP laptops that have become broken, usually with nVidia discreet video cards. Apparently the solder used when built degrades over time and micro honeycomb patterns develop in the solder causing power transmission fluctuations and resulting in bsod's and eventually black screen failure to POST. You literally remove the motherboard, strip meltable parts off it after removing the CPU, and bake it in an oven. The recipe for baking temp and time varies. Google "reflow laptop oven" to learn more.
 
The proper fix is to lift the GPU and re set balls and put it back again.


Reflowing + Adding some flux my help for some time ... but its not a permanent fix.

I would not put a motherboard in to oven .. You can pickup cheap refflowing stations ... they are worth what you pay for it ... but its way better then oven, heat gun etc...

They fail due to thermal stress and due to PB free solder
 
If cristalised (crummy) lead-free solder joints is the cause, re-flowing won't fix the problem (well, maybe temporarily).

The proper way to fix these problems (quite involving IMHO) is to have re-do the solder with lead-based low-temp solder paste and the need of a proper reflow station.

Not something I'd bother to tackle (yes, I do SMD repairs and have hot air table also, short of buying a reflow station).

Q.
 
All of those chips are pretty old by now, it's worth the oven trick but not much else.
 
It never lasts. It'll buy you a bit more time but that's about it. They are not worth fixing. The amount of time invested into resurrecting it by actually fixing the board in the style Quest mentioned is worth more than a new laptop.
 
Yeah, my DV7-2270us has the ATI videocard (Radeon HD4650 1gb vram onboard), and supposedly the problem is more prevalent among DV's with a nVidia card. But mine still has something going on. It was flaking out bigtime and then eventually stopped recognizing half of it's ram. 4gb installed, and eventually it started indicating only 2gb. As soon as it started showing only 2gb installed it went back to being stable. A sodimm must have died, so I bought a new set of 2x2gb. Stable for about a week then the same bsod's and black screens started returning but much fewer and farther between. When messing with the ram modules I noticed that the 2nd ram socket on the motherboard that sits stepped under the 1st one, the module went in much looser feeling than the module in the first socket went in. I have some Stabilant 22 on hand and put some on the contacts for the modules and re-installed. Stable for a few days but lately some random bsod's and black screen's are showing up.

So, I'm not sure what's going south inside the thing. If it was solder on the board somewhere it would seem that changing out the sodimms with new ones should not have made any difference. Unless it could be solder in the pathway to the memory sockets going bad and there exists a relationship to the amount of resistance encountered at the SODIMM-to-socket contacts that triggers conductivity faults in the failing solder.

I'll probably keep using it until the errors become too frequent, then I'll need to get something else.
 
Charlie's original article: http://www.theinquirer.net/inquirer/news/1004378/why-nvidia-chips-defective

Generally, it is easier to "bake" notebook/laptop boards as there is less plastic, and less non SMD capacitors to damage with the heat. The preferred way to reflow (amateur way that is) is to use a heat gun, and heat the chip directly while masking off the rest of the board with aluminum foil. All you are worried about is the solder balls under the silicon, not the package to board solder joints. You can use an IR thermometer to ck the heat of the chip while you work.

As stated above, this is not a permanent repair. Sometimes they last a month, a year, sometimes it just doesn't work at all. I look upon it as a learning experience with more upside than downside.
 
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