Alex VenzSep 5, 2024
Graham Sutherland / Polynomial

thread in which I talk about why the "wrap your games console in a towel" or "reflow the bga" thing works to fix some consoles, and it's nothing to do with solder balls.

https://chaos.social/@gsuberland/113084336056277361

Graham Sutherland / Polynomial (@[email protected])

@[email protected] right. there are three main types of capacitors used in consumer electronics: aluminium electrolytics (and their fancy polymer cousins), solid polymer (tantalum), and ceramic (more specifically multi-layer ceramic, or MLCC). the aluminium electrolytics are the bigbois, lots of capacitance. good for bulk energy storage. bad at higher frequency stuff. the fancy alupoly ones are for higher ripple currents. tantalum are a middle ground. low voltage, high capacitance density.

chaos.social
Sep 5, 2024 at 10:43amWeb
Show threadGraham Sutherland / PolynomialSep 5, 2024
after that supreme nerdsnipage I am going to sleep
Show threadscySep 5, 2024
@gsuberland nerdsnipage is an anagram of penis dragen
Show threadMike LynchSep 6, 2024
@gsuberland extremely good infodump, cheers
Show threadNicolas Le GlandSep 5, 2024
@gsuberland infodump 
Show threadRichard "RichiH" HartmannSep 5, 2024
@gsuberland is that where you store the solder
Show threadMarc JacobsSep 5, 2024

@gsuberland AFAIK there was a materials problem with solder joint reliability that caused Red Ring of Death. Or, if it was a capacitor problem, the caps were on the BGA itself and not on the motherboard.

This is based what people were oddly quiet about, and who was quiet.

Show thread9namesSep 5, 2024
@trollball @gsuberland https://youtu.be/z2d6IMBS8oY?t=1148
this is publicly confirmed as the root cause for the high rate of RROD in early xbox360's
- YouTube

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Show threadMarc JacobsSep 5, 2024

@9names @gsuberland They skim over that it was a temp cycle failure between the die and the BGA substrate, on a FCBGA. Not between the BGA substrate and the PCB.

The video makes it sound like temp cycling is an odd thing to cause failures.

Show threadMarc JacobsSep 5, 2024
@gsuberland Which is not to say your bit about ceramic capacitors is incorrect. I am a chip guy not a ceramic person.
Show threadI’m 481 PhonesSep 5, 2024
@gsuberland this has got to be a fork of Hanlon’s razor. Maybe: Don’t attribute to the frustration of BGAs that which can be attributed to penny-pinching?
Show threadvxoSep 5, 2024
@gsuberland wow! just when I thought I could trust MLCC's
Show threadBrian CampbellSep 5, 2024
@gsuberland Wow, what an infodump! Nice.
Show threadgudenauSep 5, 2024
@gsuberland This is some really cool information, thanks for sharing!
Show thread tonic Sep 5, 2024
@gsuberland "wake up babe new graham sutherland infodump just dropped"
Show threadHenning Paul DC4HPSep 5, 2024
@gsuberland yeah, I've been through that before. Circuits with changing phase responses around the lower cutoff frequency because of X7R DC blocking capacitors (just don't) that get reverted by removing the cap and soldering the exact same one back in. Different behavior over different voltage ratings in the same package from the same manufacturer...
Show threadVenia Silente  Sep 5, 2024
@gsuberland Wow reading this infodump recharged me! That was really fun and brought me back some memories from my first years in college (where we *both* had gaming consoles on the regular *and* did some electronics experiments on government dime).
Show threadGames That I MissedSep 5, 2024

@gsuberland Thank you! I remember the "reflow the solder balls" solution being suggested for Nvidia GPUs (I had a potentially affected laptop, but never had the problem arise). It seemed nonsensical that you could achieve the same result as a hotplate just by hotboxing a console with some towels, but I never had an Xbox 360 so never looked into it.

Even 15 years later, I appreciate you explaining what was really going on.

Show threadChap LovejoySep 6, 2024
@gsuberland great thread. Thanks for posting. This is the first explanation of capacitors that has ever made sense to me.
Show threadrecursive 🏳️‍🌈Sep 6, 2024
@gsuberland TIL there is an longer term aging thing with the type II ceramics! I knew the DC bias and temperature tolerance stuff
Show threadShark AttakSep 10, 2024
@gsuberland
Years ago I opened a RRODed Xbox360 to attempt a cap change, as it was the popular solution. I should've stopped when i saw the thin cardboard square between the die and the heatsink, but tried anyway cause it belonged to a friend. (was still ded, of course)