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I just fucking hate BGAs* that unsolder themselves.

So, thanks to my laptop slowly breaking apart I decided to reactivate an old netbook my father gave me back in 2014(?) when it failed, to have a device on standby if necessary.

Wasn't really planning to repair it and kept it for spare parts mostly as the whole device is a fucking design failure concerning heat dissipation.

But yet again, I thought I'd give it a try one-two years ago. I soon found out it was said heat problem that caused the error in the device and it'd probably only take some reworking using a heat gun, which I did. Netbook worked for some hours, then was dead again, same error. Lost motivation and stashed it until this week.

Reworked with a hair-dryer this time and it worked! Well, until this morning - same error. Perhaps I shouldn't have tried to run a VM and then shut down the device right after that.

I will now try only one more time, this time just baking the whole damn main board thoroughly.
Either it works or it's really dead after. Either way, I'll be somewhat happier then.

* Ball Grid Array - package type for electronic components like ICs/uControllers

Comments
  • 2
    Putting it in the oven should help.
  • 6
    Louis Rossmann (youtube) says it's never about the balls but the chip itself. And that the heat will fix the chip momentarily. This would explain if it stops working even after a reballing.

    Dunno if he is correct or not.
  • 3
    https://youtu.be/E9aZZxNptp0

    Alert: bad sound quality, rant
  • 0
    @electrineer Well he's not wrong, it depends on the chips' design, though. Also, he's right about a temperature of <200°C being too low.
    Thing is, and that's why I don't think this fully applies here, I wouldn't expect the device to work after two times "zombifying" (as per his word choice) it while at the second time having it work even longer than the first time.

    @Condor
    No. While you're right about subjecting the components to more thermal stress is a risk, please be aware that hand soldering and reflow soldering use typically different solder types with different physical properties. For reflow soldered components you'd typically have a temperature curve between 200-230°C to get the solder from a near-liquid to liquid state and back.

    Aye, I tried changing from laptop to tablet also, but it didn't work out. Too much of a laptop person, I think. ARMs are great though. :)
  • 0
    @NoMad Nothing yet, wanted to check out the real temperatures and their variety of my oven with the help of some sensors first. Atm patching up laptop with more duct tape.
  • 2
    I worked electronics manufacturing for about four years and BGAs were always a bitch to deal with. I wish you luck with your endeavor, but agree with @electrineer in that it's most likely the chip that's bad, not the solder point.
  • 0
    @RiderExMachina Thanks.
    If it doesn't work out, which I'm kind of expecting, there's nothing to lose really.
  • 1
    I actually tried reballing a chipset years ago with the cheapest ebay-gear there is. The reballing itself looked surprisingly nice, but I screwed while clearing the old solder from the motherboard. I probably had seen someone on YT drag their solder wick on the pcb and so I did the same and suddenly half of the pads were missing.
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