I am trying to get a grasp of how to identify what power standards various PSUs 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 PD3.0. 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?
It seems Dell is banking on consumers not being keen to read the label. According to the blogger:
The odd thing is that it is advertising itself as a 96W adapter (20V/4.8A) which is different to the printed 20V/5A rating on the rear.
So it seems has Dell decided that if they do not benefit from advertising a capability, they might as well not mention it and downplay what it can do, for legal purposes.
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?
Got nothing for you but I have to say im here to see posts like this. I often talk about blocking and wanting to filter out content and folk will talk about bubbles. Its not trying to be in a bubble its about trying to pair down whats out there so instead of seeing a post throwing and link with no context out im seeing this sorta neat thoughtful thing you were wondering about. Its an interesting thing and the responses are interesting.
This is so frustrating because it will not charge the steam deck at 45w, despite being more than capable. And of course if I use a different, capable, power supply on the laptop, it complains about low wattage
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
Edit: remember that companies need to pay fees when they advertise with the standard - they can just follow its spec without advertising it at all, I can see that happening for laptop producers specially as they don’t sell their power units as generic products (i.e. with a focus to market them).
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 to target. Even if they use PD3/PPS, if they don’t label it, don’t claim it, they never have to deal with lack of compliance.
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.
Isn’t that nonconformant?
Not to my knowledge. PPS remains an optional protocol in the standard. Why this is reasonable…
PPS offers the most granular realtime PD adjustments of not only voltage (in tiny 20mV steps) but also of current delivery (at I think 50mA increments but don’t quote me).
This is why it’s typically required by manufacturers for their fastest device charging speeds. PPS allows the most precise matching of power delivery to what BMS reports cells can absorb with little to no onboard power conditioning and minimal waste heat.
It’s a premium rating beyond standard compliance.
ETA: Confirmed. A potentially interesting follow-up question would be whether the laptop’s mainboard PDO tells you the laptop supports PPS even though its power brick doesn’t.
I appreciate the link. I wanted to see what you saw, so I opened the ZIP file and it expands to 27 files. I believe the relevant file is
USB_PD_R3.2_V1.2_2026_05_20.pdf, page 42, which states:3.2.5.2. SPR Programmable Power Supply (PPS) Programmable Power Supply (PPS) is Optional. When included, the voltages and currents a PPS Shall support are as defined in Table 3.4.
If it’s optional in rev. 3.2, I assume it’s optional in rev 3.0. I’m a bit astonished because PPS is probably the most signficant feature of rev.3. The industry is not competent enough to even tell consumers which rev a device conforms to. But if it did, typical Wikipedia-informed consumers who see PD “rev.3” advertised would naturally expect PPS. As you are correct that PPS is indeed optional, many consumers will get burnt by the misunderstanding.
A potentially interesting follow-up question would be whether the laptop’s mainboard PDO tells you the laptop supports PPS even though its power brick doesn’t.
What’s PDO?
The problem seems to be that a laptop could be designed to /need/ PPS, e.g. if the voltage it needs is well below 20v. While most PSUs do not advertise USB-PD 3(+) compliance, much less PPS.
What’s PDO?
Power Data Objects are sent by the device to the host (in this case your power supply) containing information about device capabilities and requirements.
The problem is that a laptop could be designed to /need/ PPS
This would be highly unusual, especially for a Dell workstation laptop. Some laptops can use PPS for better internal power efficiency and battery charging rate, but I know of none that require it. The feature is also leveraged far more often in small sealed devices where waste heat has basically nowhere to go, so if any device were to actually require it, I would look to small wearables. In fact, while I haven’t checked and don’t know, I’d wager many smart watch chargers are PPS enabled, which would explain their oversized connectors.
