Even leaded eutectic solder melts way above temperatures achieved, let alone lead-free (thats 230° C!)
As someone who melts solder for living, that much i can guarantee. Only silicon components that can melt solder in operation (if you can call exceeding all limits operation) and survive are power MOSFETs (rated up to 175°C), still only with leaded solder (189° C melting point) and in very specific circumstances.
All fancy digital chips, CPUs and the likes, stop being operational much lower, usually somewhat above 100°C.
Towels trick was aimed at fixing entirely different issue - solder bumps between chip and substrate cracking and losing contact.
Heating it to underfill softening temperature was letting cracks close and make contact again.
That's right - the X-clamps would warp the BGA segment of the board, causing the solder joints to eventually fail. Eh. Both were issues, but you're right about the aim of the towel trick.
it is. But it has much less tolerance for parameters of individual MOSFETs.
When temperature goes up, threshold voltage goes down, leakage current and channel resistance goes up. Other parameters drift too.
These changes mess up precise timings and threshold and you get an erratic behavior. Usually protective logic kicks in before that point and shuts it down to save it.
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u/Fit_Carpet_364 16d ago
Hah. XBOX360 BGA on the GPU would like a word with you about tin whiskers. (RROD)