I am trying to get a grasp of how to identify what power standards various PSU claim to conform to. The label on this Dell PSU is ram-packed with info, but I see no direct claim that it supports USB-PD at all.
The range of voltages might imply that perhaps maybe it’s USB-PD, but I see no indication where they take credit for that; much less a particular PD revision. IIUC, that means if it’s USB-PD non-compliant and someone drags Dell into court, they can say to the judge “we never said it was USB PD-compliant”.
The review that probes this thing shows that the PSU is detected as PD3. Yet at the same time it does not support PPS according to the blogger. So wtf… how can it be PD3 if it does not support PPS?
The blogger goes on to test it with all kinds of fancy costly gear that no typical consumer would have. When I am at a street market rifling through a pile of dumped electronics, how do I know what I am looking at? Do any of the cryptic symbols on that Dell label suggest USB-PD?
hubertmanne@piefed.social@piefed.social
Scipitie@lemmy.dbzer0.com 6 hours ago
Counter question: where does it say on there that it’s PD3.0?
From the power source it looks like PD2.
Perhaps it follows since stuff from the PD3 specs and that’s why that tester said it, but this is guesswork.
Perhaps I’m misunderstanding you but the gist of your text is “why is this item not saying what a random guy said it should say??”
I’ve checked another Dell power plug, they don’t claim anything on the box concerning standards they follow from what I can tell. Third party ones often do though.
My Lenovo doesn’t say anything about that either interestingly, thanks for the rabbit hole! :D
Onomatopoeia@lemmy.cafe 6 hours ago
As best I can find, there’s no logo/mark to indicate compliance with PD3.0, nor for PPS.
If it’s compliant with those, I suspect it’ll be in the documentation.
You’re probably on the right track - they designed this for their devices, will publish what it can do but not claim compliance with a spec they didn’t build specifically too.
In the High Level Design meetings (or equivalent), they probably laid out charging time/performance requirements which included using exsiting commodity tech and general conformance to USB C.
This so any PD compliant charger could charge the laptop, but their own charger would follow it’s own specs.
daveyOsborn@infosec.pub 4 hours ago
Nowhere. I found no mention of PD anything which inspires some of my questions.
That’s indeed the sort of answer I was looking for. The testing device detects PD3. This somewhat suggests that electronically the PSU identifies itself as PD 3.0-compliant.
I want to understand the contradiction. The testing device declares that the PSU is PD3. But the test results led the blogger to claim it’s not PPS. So where is the lying occuring? I expect the PD protocols to establish a handshake whereby each side of the handshake discloses the PD revision it adheres to. Otherwise the protocol is quite shitty.
That’s interesting. I suppose the fees finance a certification effort. And I suppose that’s fair enough. But if a device claims to be PD3 not on the label but makes this claim in the electronic protocol, the claim is a claim nonetheless. And I suppose it’s legally dicey. Dell could not be easily prosecuted for false advertising if they wrote nothing on the box or label that a buyer would see. But the hardware is still lying about its capability and I would think that would (or should) have consequences.
Onomatopoeia@lemmy.cafe 6 hours ago
I think you just said what I was trying to say, only you said it more clearly. Haha