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Robin Robin is offline
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Default USB power question

On 22/02/2021 09:50, 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.

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).


I don't think stand-by power consumption is part of the ATX or 80 plus
standards but the 4 year old PSU driving this post claims less than 0.25
watts.

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Robin
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