Testing a BGA - Good or Bad?

[senchire]

Re: Testing a BGA - Good or Bad?

Its always better to let the board gradually cool down the with a fan, at least its how i do it. After using 225-230 and getting to melting point you don't wanna get the chip in few sec under 100, also (everyone has his own way) at peak and after nudging i hold it at melting point 15-20 sec, after that i go to 190-200 and hold it there for another 2 min then let it cool down.

[Th3_uN1Qu3]

Re: Testing a BGA - Good or Bad?

Its always better to let the board gradually cool down

Yes. It creates stronger joints if you let the board cool by itself.

[vmartins45]

Re: Testing a BGA - Good or Bad?

I use this process.
Hote air at 350cº at de rear of the board , the back of the chip, for 30 seconds at 3,5cm of distance.
Alloy to cool completely, if image appears to follow rebailling.

[spidey]

Re: Testing a BGA - Good or Bad?

i apply some flux, then i use bga machine with the same profile what i use while soldering chips. But never lasts 5 months.

[Th3_uN1Qu3]

Re: Testing a BGA - Good or Bad?

i apply some flux, then i use bga machine with the same profile what i use while soldering chips. But never lasts 5 months.

With G84/G86/6100/6150/7200/7300/NVS110/NVS120 it's the luck of the draw. The only permanent solution is to replace with new chips. Not worth the pain to reball IMHO, it's still gonna fail in a few months, and the customer will not be very happy.

Other chips (especially on desktop boards) can be just reflowed and they'll last a long time.

[senchire]

Re: Testing a BGA - Good or Bad?

Ati 3xxx also last long as well as 4250 after reflow. Speaking of nvidia specially G84/86 if done properly with good flux and good machines can last long (read 8 month once).
I also don't have "professional" gear for this job, but reflow with "heat gun" and "properly controlled station isn't the same". Lets say who is more into this will say i agree but most beginners won't agree (i once also taught that my work with heat guns is near the perfect point, after getting a PH and rework station i told to my self what the crap did i do earlier).

My point is as much i agree with the college above me with his post "it's the luck of the draw" i also can say "there is a portion of skill that makes the difference on these chips even if they are a fail series" .

[sasser]

Re: Testing a BGA - Good or Bad?

Anyone can verify are this ati 216-0674026 datecode 2011 is false? Factory stop produce till 2010 and how about some reseller sell datecode +11? I use datecode 2011 till now not success. Anyone have an issue with this bga

[whaldsz]

Re: Testing a BGA - Good or Bad?

Anyone can verify are this ati 216-0674026 datecode 2011 is false? Factory stop produce till 2010 and how about some reseller sell datecode +11? I use datecode 2011 till now not success. Anyone have an issue with this bga

i'm working on this chip, i figured it needs a reball. will let you know if it's a success.

[sasser]

Re: Testing a BGA - Good or Bad?

i'm working on this chip, i figured it needs a reball. will let you know if it's a success.

Oh u means buy and reball again? I buy and replace with this chip for compaq cq40 no blinking afterthat seem like ok but all laptop i replace with this chip no display. Thanks remind me to reball

[whaldsz]

Re: Testing a BGA - Good or Bad?

Before i pull this chip, there was a short in one of the coil. The short went away after i removed the chip. I reballed and reattach the chip, the short came back. I guess it needs replacement.

There must be a way better way to test the chip if reball is all that is needed or replacement.

Do you guys always replace for certain laptop models or reball even if the mobo has no display after light reflow?

[sasser]

Re: Testing a BGA - Good or Bad?

i heard some bga buy from reseller on aliexpress must reball fisrt before use. maybe oxided .i have buy bga with datecode +11 but not success after replacement still no display.

[whaldsz]

Re: Testing a BGA - Good or Bad?

Then could it be that the problem is not related to the chip?

I am thinking that if the chip is new and the right profile is used to attach the chip to the mobo then the "no display" error should be fixed right?

[siddiq]

Re: Testing a BGA - Good or Bad?

I use a mastech Ms8217 multimeter with automatic resistance checking which gives me accurate readings and after reflowing or reballing, I test the resistance across the capacitors on the bga and if any of them read absolute zeros, then either the bga is a goner or a solder ball short has occurred underneath. Some capacitors can read as low as 3.6 ohms and that is okay, but if you get 0 ohms then either some of the balls underneath has shorted or the chip itself. But to really ascertain if the the bga is gone you need to unsolder it from the board, clear all the solder underneath and check the capacitors for shorts. Like you guys are saying, it is always best to replace with a new chip. Hope it helps...

[sasser]

Re: Testing a BGA - Good or Bad?

Then could it be that the problem is not related to the chip?

I am thinking that if the chip is new and the right profile is used to attach the chip to the mobo then the "no display" error should be fixed right?

im use same profile for another gpu. but still not success. common new bga unleaded solder ball with max temp 180c. but with datecode +09 +10 then can be use. i dont know why coz no idea to check either bga is good or damaged after replacement process done

[sasser]

Re: Testing a BGA - Good or Bad?

ICH and GMCH also is BGA type any tips to test this bga. this common problem also in motherboard repairing. what to do ? when this problem are 3.3v 5v is presented?