Why two power ports on a budget laptop??
#41
(08-10-2020, 11:43 AM)dsimic Wrote: Totally agreed.  However, the only trouble with the first requirement would be that the simple barrel connector pretty much couldn't be used any more. Smile  See, a "barrel-style" power adapter couldn't be "dumb" any more, it would instead have to be able to communicate its wattage with the laptop.  By the way, the battery inside the PBP actually isn't limited to 3 A during charging, it can take 5 A easily.

I'm not entirely convinced that is necessarily the case - e.g. that same W510 I mentioned running off 90W PSU thinking it is a 170W PSU. The PSU in ThinkPad has three lines - ground, power, and "signal". The simple resistor in the PSU connector between ground and "signal" is what tells the laptop how much power the PSU is supposed to be able to provide. When I shorted that pin on the motherboard that told the machine the PSU is a 170W model, but the machine still wasn't drawing all 170W to power the machine and charge the battery, it was drawing only as much as the PSU was actually able to provide. AFAIK the older PSUs in ThinkPads from before Lenovo acquisition do not have third signal pin, it's only power and ground, and they did come in varying power yet they were (mostly) perfectly interchangeable - e.g. I am able to use my old R50 with a 30W PSU from my 701C instead of the proper 72W, and while it doesn't charge the battery unless the laptop is pretty much turned off it does slow down the battery discharge. Something I'm not noticing with PBP (not to bash - just stating the fact).

And to be clear, when I was talking about 3A charging limit I was not talking about battery's theoretical capability, I was talking about the actual circuitry in PBP.

(08-10-2020, 07:21 PM)dieselnutjob Wrote: So I think that I am entitled to believe that the usb-C ports on these phones are not as tough as the barrel sockets that still work on some of my truly ancient laptops (Compaq NC610 with a real parallel port anyone?, or IBM Thinkpad T23? or how about a Toshiba Tecra 800 that still works as a Bosch KTS diagnostic computer, last update in 2007).

How about an IBM Convertible that's almost as old as myself? I still have one, it's banged up, with cracked plastic and broken lid latches but the power still works perfectly, though I did have to rebuild the battery. It's one of those that still boots to BASIC if there is no floppy disk with OS.
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Messages In This Thread
RE: Why two power ports on a budget laptop?? - by moonwalkers - 08-10-2020, 10:09 PM

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