On 22/02/2021 11:14, Dave Plowman (News) wrote:
In article ,
Adrian Caspersz wrote:
On 22/02/2021 09:14, Brian Gaff (Sofa) wrote:
The whole point though is for that to also be a charger, though I have to
say I'm not greatly impressed with their efficiency.


To support the ATX soft start button and wake-on-LAN features, PCs have
long offered a permanent 5V standby supply.

Yes.

So this USB powering thing is using something that was already there as
an independent subsystem. This would be as efficient as a typical
plug-in wall adapter (I'd hope).

But if you'd something like an external HD plugged into USB, does it make
sense for it to be powered 24/7?


USB-powered external HDDs will usually enter sleep mode. If your webcam
doesn't perhaps that's because it consumes negligible power when not in
use. What do the specifications say?


PS
I routinely leave my phone charging from a PC overnight when speed is
not of the essence.

--
Robin
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