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

[Th3_uN1Qu3]

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

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

Hundreds of service manuals and schematics. Generally, most Dell laptops do support external video card when docked. Other brands rarely do, only in business class laptops.

"Reflow" , you mean giving the chip a heat shoot without replacing?

Yes.

Undervolting ? How ? I haven't seen such option in my BIOS !

Hardware modification of the power supply feedback circuit. It's simple actually, 1 single resistor needs to be changed. Finding it is the challenging part.

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.

Should do for a one-off. You'll also need some sort of support to keep the hot air gun in place. And don't forget the thermocouple.

Preheat to 150C, take it to 217 in 30-40 seconds. Hold that temperature for 30 seconds. Take it to 235, 240 max. It should not be over 220C for more than 15-20 seconds or you risk permanently damaging the chip. In your case, the thermocouple should be on top of the BGA die or right next to it.

Would a reflow work for such a problem ?

Unless you run it too hot and fry it, it will work 100%. But it is always a temporary fix. Like i said, if you also undervolt it, it may last more than 6 months.

[hary66]

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

Hi back.

Would you give me some advice to choose/buy flux and other stuff I would need.


It seems there are different quality flux and solder wick. What would you advice from Ebay for instance. (by the time, Ebay is my main electronic supplier because is cheap from China !)