Motherboard malfunction - a possible warning about power supplies
#1
A computer repair shop tells me my PBP's mainboard needs replacing. Since they cost $99 + P&P on the official store, and they're currently out of stock anyway, I'm planning to get a new machine instead.

The problem I brought the machine in with was that, after a minute or so of a whining/buzzing noise one evening, all inputs - keyboard, mouse and USB - stopped working simultaneously. The machine could power on and off, and load the login screen, but I couldn't interact with it.

On opening it up, the repair guy spotted an area of discolouration, possibly some melted plastic, and a blob of solder on a chip, which he interpreted as signs of a component having blown. I'd been charging the machine from a power supply rated with three ratings, of which one was correct (5v, 3a) and the other two were not; and he guessed that the machine had sometimes been switching to off-spec ratings, as its power usage went up and down, and that over time this had caused damage and eventually failure somewhere in the motherboard.

If the guess is right, then I guess this is a caution not to use power supplies with multiple ratings.
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#2
It sounds like the 5 V regulator on the main board went kaput, because it provides power to USB devices, which includes the keyboard and the touchpad.  Speaking of power supplies, nothing catastrophically bad should happen as long as the supply provides exactly 5 V.
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#3
(07-28-2021, 12:01 PM)dsimic Wrote: It sounds like the 5 V regulator on the main board went kaput, because it provides power to USB devices, which includes the keyboard and the touchpad.  Speaking of power supplies, nothing catastrophically bad should happen as long as the supply provides exactly 5 V.

The power supply is printed with "OUTPUT: 5V == 3A or 9V == 1.6A or 12V == 1.2A", so unless it was misprinted or malfunctioning it should have offered exactly 5V when requested.
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#4
Is that a USB Type-C charger?
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#5
(07-28-2021, 12:15 PM)dsimic Wrote: Is that a USB Type-C charger?
A to C; designed for a smartphone.
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#6
Well, if it wasn't a PD (Power Delivery) charger, then we might have found the reason for your issues.
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#7
(07-28-2021, 12:20 PM)dsimic Wrote: Well, if it wasn't a PD (Power Delivery) charger, then we might have found the reason for your issues.

I'm not sure how to tell, but suppose it wasn't. How would you expect that to cause a problem?
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#8
If the charger has a Type-A port on it, then it isn't a PD charger. In a few words, when you connect something that can provide multiple voltages to the Pinebook Pro's Type-C port, that thing and the Pinebook Pro need to negotiate the right voltage, and the only way for Pinebook Pro to do that is using the PD protocol.
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#9
(07-28-2021, 12:29 PM)dsimic Wrote: If the charger has a Type-A port on it, then it isn't a PD charger.  In a few words, when you connect something that can provide multiple voltages to the Pinebook Pro's Type-C port, that thing and the Pinebook Pro need to negotiate the right voltage, and the only way for Pinebook Pro to do that is using the PD protocol.

OK, that's good to know. Thanks.
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