[ltp] T530 Claims Wrong Powersupply

Bjørn Mork linux-thinkpad@linux-thinkpad.org
Tue, 28 Feb 2017 21:43:20 +0100

Henrique de Moraes Holschuh <hmh@hmh.eng.br> writes:

> On Tue, 28 Feb 2017, Joerg Bruehe wrote:
>> This morning, I got a message on booting which I've never seen before:
>> Before it showed the grub menu, the system claimed that the power supply=
>> a lower wattage than expected, and required that I hit Esc to continue.
> Yeah, it uses an idiotic trick to detect power supply size.
> http://forum.thinkpads.com/viewtopic.php?t=94554&start=90

Wow, that's interesting.  I suspect that explains the issues I have with
a barrel-to-square adapter and an old 65W power supply.  It mostly works
with my X1 Carbon, but intermittently stops charging in the "middle"
charge area where the power drain will be highest.  I have never
understood why, since the original 65W X1 power supply has identical
specs and looks pretty much the same as the old one, except for the
connector.  If the X1 detects the old supply as 90W due to a hard coded
resistance in the barrel-to-square adapter, then I can understand why it
is failing when attempting to "turbo charge" the X1.

OK, will have to measure these things some day.