Comment - FBXL Lotide

Comment on HP laptop rejects Dell PSU on the basis of branding.. apparently. Crappy design, asshole design, or good design?

Onomatopoeia@lemmy.cafe ⁨3⁩ ⁨days⁩ ago

Meh, those designs were to ensure you got the right power supply and didn’t fry the mobo.

It’s a little of asshole design, but it also prevented warranty issues from people using the wrong PSU.

Having been on teams depliying thousands of laptops and desktops, knowing everyone had the right power supply was important - this helped us too. End users can be oblivious and will just plug in shit willy-nilly. We only had a few spare machines, and no spare time. Imagine of using a different PSU could cause problems - we could be chasing a few rogue power supplies for days.

I’m ok with this choice, even with the bit of asshole design.

Fortunately USB C adoption is making this problem go away.

original

Sort:hotnew top

wiccan2@thelemmy.club ⁨3⁩ ⁨days⁩ ago
USB-C has been game changing for us.

I can now confidently go to any desk or meeting room in the company and be fairly certain that my laptop will just work with whatever’s been installed regardless of brands.

original
- daveyOsborn@infosec.pub ⁨3⁩ ⁨days⁩ ago
  USB PD is also a shit show. You might want to read this:
  
  goughlui.com/…/tested-usb-c-barrel-connector-adap…
  
  Which shows those USB PD negotiations can get dicey. It chooses voltages thought to be close enough to what’s requested.
  
  I’ve run into a nasty problem where a USB-C appliance needed 9v. Says in the manual something like “only use Kenwood power supplies on this device”. I thought, fuck that, USB PD is a standard for a reason. I’m not going to blow money on a proprietary OEM Kenwood USB-C PSU. Then found that many power supplies actually skip 9v. The USB PD standard makes some voltage steps optional, and some mandatory. IIRC, 9v was one of the required ones, yet it was easy to find USB-C power supplies that skipped 9v but offered 12v (or 15v, I forget). And yet 12v or 15v was one of the voltage steps that’s optional.
  
  original
  - cmnybo@discuss.tchncs.de ⁨2⁩ ⁨days⁩ ago
    12V is optional now. It was part of PD revision 1.0 and dropped in later revisions, but many chargers still support it. 9V has been required since PD rev 2.0.
    
    With the device that uses the 9V only USB adapter, I would either glue the plug in or replace it with something else. Its too easy to accidentally fry something with that.
    
    original
  - kkj@lemmy.dbzer0.com ⁨2⁩ ⁨days⁩ ago
    I’m getting the sense from your comments that you think that USB-PD will deliver a higher voltage than requested. This is not accurate. A device can request any of the voltages specified by PD, and the power supply will supply that voltage if it is capable of doing so. If not, it will provide 5V. It’s very possible to get a sippy that won’t power your device, but a working, PD-compliant power supply will not damage a working, PD-compliant device.
    
    Obviously, if you get a barrel jack adapter that requests 20V and then plug it into a 5V device, you’re going to let the magic smoke out, but that’s because barrel jacks don’t do negotiation. The power supply correctly supplies 20V as requested, and then you plug that 20V into the wrong thing.
    
    original
    daveyOsborn@infosec.pub ⁨1⁩ ⁨day⁩ ago
    
    I’m getting the sense from your comments that you think that USB-PD will deliver a higher voltage than requested. This is not accurate. A device can request any of the voltages specified by PD, and the power supply will supply that voltage if it is capable of doing so. If not, it will provide 5V. It’s very possible to get a sippy that won’t power your device, but a working, PD-compliant power supply will not damage a working, PD-compliant device.
    
    That’s not true. See the experiment I linked.
    
    Obviously, if you get a barrel jack adapter that requests 20V and then plug it into a 5V device, you’re going to let the magic smoke out, but that’s because barrel jacks don’t do negotiation. The power supply correctly supplies 20V as requested, and then you plug that 20V into the wrong thing.
    
    Of course. Not sure what point you’re trying to make here but the conversation was about whether the barrel adapter is compliant with the standards. Not whether you can misuse it.
    
    original
    -> View More Comments
  - Onomatopoeia@lemmy.cafe ⁨3⁩ ⁨days⁩ ago
    
    So I have an adsptrt that goes from battel to USB-C
    
    That’s joy part of USB spec as there’s no way to communcate requirements through the barrel. Hard to blame USB for when we side-step it’s design.
    
    I do stuff like this too, but only for devices that just need power, nothing like a laptop or with circuitry that could get fried by the wrong voltage.
    
    original
    daveyOsborn@infosec.pub ⁨3⁩ ⁨days⁩ ago
    
    That’s no part of USB spec
    
    Do you mean the USB PD spec? It does not violate the USB spec which sets a default voltage of 5v. The adapter /would/ violate the USB PD spec if it were to claim to be USB PD compliant. But the shit-show we have is that USB-C does not imply USB PD. And so the market is full of USB-C things that are not USB PD. And often they do not claim to be USB PD as consumers are not wise enough to demand it.
    
    Note as well the adapter I mentioned is quite dumb – just hardwires pins for the situation that the appliance expects 5v without negotiation. But it would be possible to implement a USB PD-compliant adaptor with the smarts to handshake, which would then refuse to complete the handshake in the event that the voltage supplied is not that requested. Of course it would be a bit strange to put that much sophistication into it which would likely drive the cost to that of a whole compliant PSU anyway (thus defeating the purpose). But notice the opposite has been done, whereby the adapter negotiates a voltage on behalf of a barrel device.
    
    as there’s no way to communcate requirements through the barrel.
    
    IIRC, it’s disputed whether the hanshake negotiation is needed for 5v. Some appliances expect to do a handshake /no matter what/, and some 5v appliances are designed to skip the negotiation entirely. If you are in the camp that says even 5v must have a handshake negotiation, then you would condemn the simple barrel to usb-c adapter (but perhaps not one that is only for a fixed input and the circuitry to do the negotiation).
    
    Hard to blame USB for when we side-step it’s design.
    
    The blame was not pin-pointed. I pointed out a shit show in the marketplace. There are bits of the standard you can blame, and you can also blame market actors. You can probably also blame regulators for not preventing the shit show that I described.
    
    original
ChrysanthemumIndica@discuss.tchncs.de ⁨3⁩ ⁨days⁩ ago
I just responded to the other post, and I definitely agree with you that when you’re working with so many systems, knowing you have a baseline for the power supplies is important! (Especially given how sketchy those third-party adapters can be…)

But I will say I think it’s pretty anti -consumer, and not accidental at all, that there is vendor lock in there. And as I said in that reply, I think a setting in the BIOS with a warning (and maybe a warranty invalidation?) that allowed it would have been the more friendly approach, but I can only imagine how much the lawyers would yell about why that’s a bad idea, haha

USB-PD made me so happy, I was using my Apple power adapter with my Surface and Dell laptops and it was great!

original
- Onomatopoeia@lemmy.cafe ⁨3⁩ ⁨days⁩ ago
  Well put.
  
  Though I’ve had little trouble using other power supplies across brands, so I wonder of this is a single HP line.
  
  I’ve never run across this in business models - if the barrel fits it works, but each brand used their own barrel design, whether that was a different size or a pin in the middle.
  
  And I’ve worked with many brands since the mid 90’s - I’ve deployed thousands of machines over the years - not to say I’ve seen all of them, but a lot of the major brand’s business models.
  
  Consumer models are just garbage, so if this happens there I’m neither surprised nor concerned. I never buy consumer models - they’re garbage, and cheaper for that reason.
  
  And now C is resolving the issue.
  
  original
daveyOsborn@infosec.pub ⁨3⁩ ⁨days⁩ ago
So in the context of copious dumb users plugging in anything that fits the socket, the data PIN likely prevented a lot of damage while at the same time enabled HP to rack in lots of money on replacement OEM proprietary PSUs. Indeed I have seen on many occasians clueless plebs at the street market selling 2nd-hand appliances and quickly trying barrels from a pile of tangled PSUs until one fits, then trying to include that with the device they are selling without looking at voltage or anything. It’s common and I’m sure lots of gear gets fried because the general population is just not smart enough.

I know how to match voltage, polarity, and current demands. And I got stung. Spent a lot of time disassembling a laptop, trying different RAM sticks, removing wifi cards and other components as I was baffled about what this fucking blicking LED means when it is not blinking in any way to convey an error code. Removed the CR2032 battery to reset the CMOS. Just got a steady non-stop blink, which the manual falsely states means it’s in sleep mode. So I was ready to conclude that the laptop was trapped in sleep mode and irreparable.

Whether it is a good design to protect from incorrect PSUs (despite that the obscure barrel connector is probably only 19.5v systems anyway), most certainly it’s a crappy design to not inform users. To fail to assign an error code. Sure, it says in the manual something like “use only approved HP power adapters” – something /smart/ consumers do not take seriously because they know that shit is a branding hussle. The data pin should not be a secret that is concealed from both the user guide and the maintenance and service guide (which HP says is not for end users… yet they still withhold the info from service people).

original