wooly wrote: ↑

Sat Nov 30, 2024 5:56 pm

ejolson wrote: ↑

Fri Nov 29, 2024 4:43 pm

Not 'refused.'
"Not recognised by the (non-existent) PD negotiation as being capable of delivering 5 amps" would be a more accurate statement.

Except under very demanding usage an RPi5 can run perfectly well from a 3 amp supply.

Here demanding means connecting any storage device to USB or a PCIe m.2 hat.

1. it start and shut down before even activating the monitor so i call it "refusing"

Maybe describe the symptoms in detail not make up an arbitrary term that none one recognises next time. If we don't know what you mean we can't help you.

2. some friends having RPI5 told that were happy with a 3A PSU they previously used on a Pi4, so i trusted them.
3. with a PD compliant 3A it works, but has problems with PCIe m.2 expansion [not hat since is not connected to GPIO] when an high rate of I/O is made.

Whether or not a 3A PSU is PD capbale shouldn't matter. The Pi5 ask for 5A@5V and assume 3A@5V if it doesn't get it or if the PSU is not PD. In which case it will restrict USB current to a total of 600mA unless configured to do otherwise (search the forum, it's come up many times over the last year).

If the board is not connected to GPIO, how is it connected? The PCIe ribbon? USB?

The PCIe ribbon supports a maximum of 1A. If your drive needs more than that it won't work reliably. Or at all.

The producer of the board when I asked how to connect to the extra 2 pins for a 5V supply replied that for memories less than 1TB the supply from the PCIe cable is enough, and this was confirmed even here, telling that since the PCIe on RPI5 uses only one lane the power requirement of the "official" ssd tagged as 2.4A were acceptable.

That claim seems more like BS on the part of the board manufacturer than truth. Yes, dropping to one lane will reduce current drawn by the device. As will running it at a lower PCIe generation. I don't see that storage capacity below 1TB guarantees low power though and expecting a 75% reduction is, in my opinion, overly optimistic.

Also the boot did not complain when booting from nvme with 3A .

So ask yourself what else changed bvetween it working and not.

It looks that it was not marked enough strong in the various documentation that the limits on power supply does apply not only to USB boot, but also to nvme boot [or using heavily the nvme after boot]
For this I was unhappy.

Not going to comment on that.

4. someone here said that I should have complained to the courier or the supplier: if i order from the local distributor I would pay 13,25€ for the PSU and 9€ for shipping (and if courier do not find me at home I have to go to collect 20 km away) or i have to collect at their shop ... 340 km away from here. My usual supplier for these devices ship for free click and collect but only for orders over 40€ [and it sell for 16€]

That was me.

As I said above:

thagrol wrote: ↑

Fri Nov 29, 2024 11:40 am

RPL don't sell direct to the public (except through their shop in Cambridge)

They sell to official resellers (and others, as do resellers) and set a recommended retail price (excluding shipping and taxes). You buy from a reseller. The reseller decides how much to charge for shipping and handling. If your package goes missing you take that up with the seller or with the delivery company (depending on local laws).

AIUI the only sanction they have is to remove a company's official reseller status. I can onyl speculate ut I suspect they'd need more than expensive shipping charges to justify that.

Your delivery problems are not specific to buying a PI PSU. They're not RPL's responsibility either.

It's also extremely unlikely that anyone on here can help resolve them or is able to do more than comfort you. "Oh dear. How sad. Never mind."

5. what happen if i connect the second exit from my PSU [that has 3 3A capable exits, up to 40W total] to some 5V point [which is better?] in the RPi5 or the M2 adapter? will the on-off switch continue to work?

Electrically speaking? I've no firm idea. What I can say is:

1. 3 x 3A@5V is a total of 45W so the PSU spec is lying to you. A 40W PSU cannot deliver 45W regardless of how many outputs it has.
2. It depends on how well each output is regulated and on other factors (like voltage drop in the cables and connectors). If the voltages are not the same on each output at the Pi, current will flow in the wrong direction.
3. Unless you change either the boot loader config or config.txt (as I said, how is in multiple places on these forums) a more capable PSU will have no effect on downstream devices (especially USB ones).

*: BSM Tudor Bryn Williams, Royal Artillery.

Knowledge, skills, & experience have value. If you expect to profit from someone's you should expect to pay for them.

All advice given is based on my experience. it worked for me, it may not work for you.
Need help? https://github.com/thagrol/Guides

thagrol wrote: ↑

Sat Nov 30, 2024 10:28 pm

wooly wrote: ↑

Sat Nov 30, 2024 5:56 pm

1. it start and shut down before even activating the monitor so i call it "refusing"

Maybe describe the symptoms in detail not make up an arbitrary term that none one recognises next time. If we don't know what you mean we can't help you.

since it does not arrive to write the log is difficult to explain.
Say that it start and immediately shut down.

If the board is not connected to GPIO, how is it connected? The PCIe ribbon? USB?
The PCIe ribbon supports a maximum of 1A. If your drive needs more than that it won't work reliably. Or at all.

PCIe ribbon. Other people had same device and afaik noone had problem due to insufficient supply (in theory should be 850mA )
Also the boot did not complain when booting from nvme with 3A .
But when using a lot due to swapping it hang
so it would explain why even if now there is a sd card to run the system, but the nvme is still in place but not used, has no longer complained.

Your delivery problems are not specific to buying a PI PSU. They're not RPL's responsibility either.

Absolutely not, the problem is for a lot of product, and for many people

Electrically speaking? I've no firm idea. What I can say is:

1. 3 x 3A@5V is a total of 45W so the PSU spec is lying to you. A 40W PSU cannot deliver 45W regardless of how many outputs it has.
2. It depends on how well each output is regulated and on other factors (like voltage drop in the cables and connectors). If the voltages are not the same on each output at the Pi, current will flow in the wrong direction.

is not lying: it has three output (one "plain", 5V/3A only, and two PD: fineprints in instructions says that the advertised 40W may be achieved only with one output at 9V/2.8A and one at 5V/3.1 A, the other possible combinations are the two PD at 9V/2A, or any two outputs at 5V/3A . Else If you use all the three you may draw a maximum of 10W each one.
About flowing in the wrong direction: it could occour in any case you supply in two points, but then the supply should be able to balance the few mV difference.

bensimmo wrote: Or bring your own 5V5A and make you own and run it through the GPIO or similar (...)
As for crashing? Other Pi models reduce/limit speed, I know the Pi3 crawls in that mode, but that's on a voltage drop. If the current ramps up the voltage may just drop too far too quickly or the PSU shuts down too.

What is official way to tell Pi5 not to go over a certain speed [say 1.8 GHz] and how many mA would shave out [would be nice since it would reduce also the average consumption] ?

Last edited by wooly on Mon Dec 02, 2024 10:14 pm, edited 1 time in total.

--
Leonardo
mailto:[email protected]

I'm not responding to everything in your last post as the messed up quoting makes it difficult to see who wrote what.,

wooly wrote: ↑

Sat Nov 30, 2024 11:49 pm

PCIe ribbon. Other people had same device and afaik noone had problem due to insufficient supply (in theory should be 850mA )

So 250mA more than the Pi5 will permit when running from a 3A PD or any wattage non-PD supply.
[/quote]

Also the boot did not complain when booting from nvme with 3A .
But when using a lot due to swapping it hang
so it would explain why even if now there is a sd card to run the system, but the nvme is still in place but not used, has no longer complained.

Well yes. Drawing too much means the over current protection cuts in, the drive loses power and your swap space and everything in it has disappeared. And the root partition if you have that on the NVMe.

Absolutely not, the problem is for a lot of product, and for many people

A sweeping generalisation if I ever saw one. You'll need some hard evidence to justify that.

is not lying: it has three output (one "plain", 5V/3A only, and two PD: fineprints in instructions says that the advertised 40W may be achieved only with one output at 9V/2.8A and one at 5V/3.1 A, the other possible combinations are the two PD at 9V/2A, or any two outputs at 5V/3A . Else If you use all the three you may draw a maximum of 10W each one.

And none of that is in the post I was responding to.

About flowing in the wrong direction: it could occour in any case you supply in two points, but then the supply should be able to balance the few mV difference.

Yes, it could. The risk is entirely on you if you try it.

What is official way to tell Pi5 not to go over a certain speed [say 1.8 GHz] and how many mA would shave out [would be nice since it would reduce also the average consumption] ?

I have no idea. You should probably start with the official documentation.

Due to the constantly moving goal posts, ignorance of basic commercial realities, and the fact we're going from general Pi5 discussion to specifics of one person's usage I'm out of this discussion. You might want to start a new thread for your specific power saving issues rather than continuing to hijack this one.

Knowledge, skills, & experience have value. If you expect to profit from someone's you should expect to pay for them.

All advice given is based on my experience. it worked for me, it may not work for you.
Need help? https://github.com/thagrol/Guides

I run a Pi5 with m.2 hat, 256GB nvme drive off a non-Pi USBC ps, that I used for testing the Pi4 before it was released and our own PS was available.So this is a 5v3A device maximum. No PD.

I get occasional low voltage warning, but otherwise it's been completely solid.

Software guy, working in the applications team.

jamesh wrote: ↑

Sun Dec 01, 2024 8:31 am

I run a Pi5 with m.2 hat, 256GB nvme (...)

Maybe the difference is that I have 500GB so a few mA more .
I have howewer to point another thing:
in the beginener section there is a STICKY thread viewtopic.php?t=83446 that is not updated to Pi5 but nevertheless is sticky, and probably is the FIRST thing people read when deciding to buy a RPi that is extremely tolerant on the choice of PSU.
It would be useful to append it with the considerations for the Pi5 ! otherwise cases as mine could reoccur.

--
Leonardo
mailto:[email protected]

wooly wrote: ↑

Sun Dec 01, 2024 11:24 am

Maybe the difference is that I have 500GB so a few mA more .

That does not say anything. At least you need to know yourself what the specification of the storage solution is. And do power budget calculation. Also please post them here.
Similar: viewtopic.php?t=380126#p2273386

ejolson wrote: ↑

Fri Nov 29, 2024 5:26 pm

thagrol wrote: ↑

Fri Nov 29, 2024 5:10 pm

ejolson wrote: ↑

Fri Nov 29, 2024 4:43 pm

Here demanding means connecting any storage device to USB or a PCIe m.2 hat.

Has the boot loader changed recently then? I though the confirm on boot was only needed if the USB device is the boot device. Even money chance I'm wrong about that though as I've not tested it.

It might be possible to override the power limits on the USB ports and pretend one has a 5A supply even when it's not and then successfully mount an external drive. Even if it works at first, the SSD could draw more power over time as it wear levels while the under-specified power supply may age and fail at the wrong end of the bathtub.

Before getting the NVMe SSD my Pi 5 was booting/running from a USB 3 connected SATA SSD. Power was a claimed 2.5A from an audio AMP HAT. Zero issues.

I could run the PCIe m.2 BASE with this setup but was getting correctable errors. Rejigging the setup and running from an official supply resolved the correctable errors.

thagrol wrote: ↑

Sun Dec 01, 2024 12:19 am

Well yes. Drawing too much means the over current protection cuts in, the drive loses power and your swap space and everything in it has disappeared. And the root partition if you have that on the NVMe.

It is exactly what happened ... not nice on pi part ... and it explains why booting from a sd card does not make the same effect.

--
Leonardo
mailto:[email protected]

wooly wrote: ↑

Mon Dec 02, 2024 10:20 pm

thagrol wrote: ↑

Sun Dec 01, 2024 12:19 am

Well yes. Drawing too much means the over current protection cuts in, the drive loses power and your swap space and everything in it has disappeared. And the root partition if you have that on the NVMe.

It is exactly what happened ... not nice on pi part ... and it explains why booting from a sd card does not make the same effect.

Would you rather have the Pi dump all the available current through a short, start a fire, and burn down your house? With no protection on the PI you're relying on the RCD or fuse in the plug or breaker panel to protect you.

You Pi does not, and cannot, know if the over current it detects is peaking at a few (tens?) of mA or it's the start of a much larger draw. It seems the designers have decided to err on the side of caution and cut power to down stream USB devices before damage can occur to the Pi, the PSU, your home's wiring, life, and limb. A sensible thing to do in my opinion.

Over current protection is not unique to Pi. Nor is it unique to computers in general. My toaster has a fuse in its plug as do most mains appliances in the UK. Dunno about where you are as you've not told us where that is.

Knowledge, skills, & experience have value. If you expect to profit from someone's you should expect to pay for them.

All advice given is based on my experience. it worked for me, it may not work for you.
Need help? https://github.com/thagrol/Guides

thagrol wrote: ↑

Tue Dec 03, 2024 2:47 am

Would you rather have the Pi dump all the available current through a short, start a fire, and burn down your house? With no protection on the PI you're relying on the RCD or fuse in the plug or breaker panel to protect you.
You Pi does not, and cannot, know if the over current it detects is peaking at a few (tens?) of mA or it's the start of a much larger draw. It seems the designers have decided to err on the side of caution and cut power to down stream USB devices before damage can occur to the Pi, the PSU, your home's wiring, life, and limb. A sensible thing to do in my opinion.

what worries me is that it shuts down current before trying other things to reduce load [such throttling] and, the louder complaint, that all documentation say the it would limit the usb output to 0,6A but no mention on the output on the PCIe bus [confirmed that if you start via USB you get on boot a loud remind, but nothing if you start from PCIe ...]
For your soul's peace: there is an overload breaker in the socket where my PSU is plugged.

--
Leonardo
mailto:[email protected]

wooly wrote: ↑

Tue Dec 03, 2024 2:18 pm

thagrol wrote: ↑

Tue Dec 03, 2024 2:47 am

Would you rather have the Pi dump all the available current through a short, start a fire, and burn down your house? With no protection on the PI you're relying on the RCD or fuse in the plug or breaker panel to protect you.
You Pi does not, and cannot, know if the over current it detects is peaking at a few (tens?) of mA or it's the start of a much larger draw. It seems the designers have decided to err on the side of caution and cut power to down stream USB devices before damage can occur to the Pi, the PSU, your home's wiring, life, and limb. A sensible thing to do in my opinion.

what worries me is that it shuts down current before trying other things to reduce load [such throttling] and, the louder complaint, that all documentation say the it would limit the usb output to 0,6A but no mention on the output on the PCIe bus [confirmed that if you start via USB you get on boot a loud remind, but nothing if you start from PCIe ...]
For your soul's peace: there is an overload breaker in the socket where my PSU is plugged.

I think it does throttle when undervoltage occurs. However, I suspect that would not be fast enough to cope with a sudden increase in power demand, and given the Pi 5 cannot predict the future, you cannot pre-emptively slow things down as you have no idea what is just about to happen.

I'm not sure that the PCIe power is specifically reduced - it's just a side effect of a lack of power to the system overall.

Software guy, working in the applications team.

thagrol wrote: ↑

Tue Dec 03, 2024 2:47 am

Would you rather have the Pi dump all the available current through a short, start a fire, and burn down your house? With no protection on the PI you're relying on the RCD or fuse in the plug or breaker panel to protect you.

wooly wrote: For your soul's peace: there is an overload breaker in the socket where my PSU is plugged.

While I entirely support having both an appropriately rated MCB (circuit breaker) and an RCD (residual current device) on every mains circuit, this will not protect against the effects of a fault on the low voltage side of a switched mode PSU. By nature these isolate the output from mains, so there can be no earth leakage faults.* While the PSU is working properly, it will limit output current to its maximum rating, but that could be enough to start a fire n the wrong circumstances.

* Note that the circuit of a properly designed PSU does "leak" some mains current to the output -- not enough to trip an RCD, but enough to give you that (safe) tingle if the entire output side is unearthed, and you are earthed, and you touch the powered equipment.... This is done so that RF interference is reduced.

Location: 345th cell on the right of the 210th row of L2 cache

davidcoton wrote: ↑

Tue Dec 03, 2024 5:40 pm

This is done so that RF interference is reduced.

I always thought that tingling was because "Das komputermaschine ist nicht für der gefingerpoken und mittengrabben."

https://en.m.wikipedia.org/wiki/Blinkenlights

Last edited by ejolson on Tue Dec 03, 2024 7:12 pm, edited 1 time in total.

jamesh wrote: ↑

Tue Dec 03, 2024 2:48 pm

wooly wrote: ↑

Tue Dec 03, 2024 2:18 pm

thagrol wrote: ↑

Tue Dec 03, 2024 2:47 am

Would you rather have the Pi dump all the available current through a short, start a fire, and burn down your house? With no protection on the PI you're relying on the RCD or fuse in the plug or breaker panel to protect you.
You Pi does not, and cannot, know if the over current it detects is peaking at a few (tens?) of mA or it's the start of a much larger draw. It seems the designers have decided to err on the side of caution and cut power to down stream USB devices before damage can occur to the Pi, the PSU, your home's wiring, life, and limb. A sensible thing to do in my opinion.

what worries me is that it shuts down current before trying other things to reduce load [such throttling] and, the louder complaint, that all documentation say the it would limit the usb output to 0,6A but no mention on the output on the PCIe bus [confirmed that if you start via USB you get on boot a loud remind, but nothing if you start from PCIe ...]
For your soul's peace: there is an overload breaker in the socket where my PSU is plugged.

I think it does throttle when undervoltage occurs. However, I suspect that would not be fast enough to cope with a sudden increase in power demand, and given the Pi 5 cannot predict the future, you cannot pre-emptively slow things down as you have no idea what is just about to happen.

I'm not sure that the PCIe power is specifically reduced - it's just a side effect of a lack of power to the system overall.

How long til the AI HATs/NPU can do that for the Pi5

ejolson wrote: ↑

Tue Dec 03, 2024 7:09 pm

davidcoton wrote: ↑

Tue Dec 03, 2024 5:40 pm

This is done so that RF interference is reduced.

I always thought that tingling was because "Das komputermaschine ist nicht für der gefingerpoken und mittengrabben."

https://en.m.wikipedia.org/wiki/Blinkenlights

That too. :lol: (First saw that poster near a college mainframe c1976, when I was learning Fortran. Seems it goes back two decades further than that.)

Location: 345th cell on the right of the 210th row of L2 cache

since some week ago I posted some cries about my problems I update you:
I manage to get a Raspberry PSU with free shipping, even if took 9 days to arrive .
with it it is much more stable and could do also some measurement, so it looks that the nvme board I have sucks about 800 mA (the producer said 750 to 850) when heavily loaded.
But at least with the nvme on pcie the perceives speed in normal use is on par of the one of my current laptop [i5] .

--
Leonardo
mailto:[email protected]

Whatever happened to the POE HAT+ (Pi5 Edition) ?

Here is all the design talk form October 2023, about 70 weeks ago, but as far as I remember it never appeared.

So either demand is not deemed there, or someone forgot about it, or getting a reliable and stable 5A is a problem.
(It was also missing from the Pi500 product but is on designed on the board so that may rule out demand)

https://www.raspberrypi.com/news/design ... etworking/ to refresh your memory. This is now quality 'Vapourware' ?

there are other products 'still missing' - 5in DSI screen i.e.
Most likely priorities have changed - or some issues need more time to be sorted.

bensimmo wrote: ↑

Sun Feb 09, 2025 8:40 am

Whatever happened to the POE HAT+ (Pi5 Edition) ?

Here is all the design talk form October 2023, about 70 weeks ago, but as far as I remember it never appeared.

So either demand is not deemed there, or someone forgot about it, or getting a reliable and stable 5A is a problem.
(It was also missing from the Pi500 product but is on designed on the board so that may rule out demand)

https://www.raspberrypi.com/news/design ... etworking/ to refresh your memory. This is now quality 'Vapourware' ?

The Pi 4 PoE hat claims 802.3at and 4A at 5V suggesting 20W when the standard specifies 30W. I recall I used to drive one (on its own) with no problems from an af switch port. So I would guess everything needs to be chunked up a bit to reach 30W with a bit of margin for tolerance.
There is at least a design in principal, the shadow of which can be seen on the PCB silk screen of a Pi500.

It can be seen in the release of the Pi5 and talked about in the Video blog post linked before.
Not just a shadow.
https://www.raspberrypi.com/news/introd ... erry-pi-5/

It was real, it's just vapourware now ;-)

I have 2 raspberry pi 5's. ! has the Hailo AI kit. The 2nd has a PI camera attached. Icouldn't get the Hailo KIT to work with the camera as I was putting it into a metal case and it was shorting out. Why not use a 3D printed case. Coz I already bought a metal one. Why can't we use Docker with multiple resources to run our PI's. It keeps giving me errors. Either *** NO CAMERA DETECTED *** or no PCIE detected... You know what I'm talking about. Isn't this 2025. Aren't we on the brink of AI Humanoid robot and domination. Why is 1 tiny little thing holding us back? And for F%ck sakes.. stop showuing me foxes!!

mjlevey wrote: ↑

Mon Apr 21, 2025 1:49 pm

I have 2 raspberry pi 5's. ! has the Hailo AI kit. The 2nd has a PI camera attached. Icouldn't get the Hailo KIT to work with the camera as I was putting it into a metal case and it was shorting out. Why not use a 3D printed case. Coz I already bought a metal one. Why can't we use Docker with multiple resources to run our PI's. It keeps giving me errors. Either *** NO CAMERA DETECTED *** or no PCIE detected... You know what I'm talking about. Isn't this 2025. Aren't we on the brink of AI Humanoid robot and domination. Why is 1 tiny little thing holding us back? And for F%ck sakes.. stop showuing me foxes!!

???

bensimmo wrote: ↑

Mon Apr 21, 2025 6:31 pm

mjlevey wrote: ↑

Mon Apr 21, 2025 1:49 pm

I have 2 raspberry pi 5's. ! has the Hailo AI kit. The 2nd has a PI camera attached. Icouldn't get the Hailo KIT to work with the camera as I was putting it into a metal case and it was shorting out. Why not use a 3D printed case. Coz I already bought a metal one. Why can't we use Docker with multiple resources to run our PI's. It keeps giving me errors. Either *** NO CAMERA DETECTED *** or no PCIE detected... You know what I'm talking about. Isn't this 2025. Aren't we on the brink of AI Humanoid robot and domination. Why is 1 tiny little thing holding us back? And for F%ck sakes.. stop showuing me foxes!!

???

Welcome, new user?

Oh no, not again.

Tip for Chromium users who watch Youtube videos. Go to the chrome://flags settings menu, and enable Vulkan as the graphics backend. There's a slight improvement with dropped frames for 1080p 60fps content.

Image

BrotherOrchid wrote: ↑

Tue Apr 29, 2025 10:53 pm

Tip for Chromium users who watch Youtube videos. Go to the chrome://flags settings menu, and enable Vulkan as the graphics backend. There's a slight improvement with dropped frames for 1080p 60fps content.

Image

Nice sharing, thanks. Will give it a try to see if it works.

Raspberry Pi OS (64-bit) with desktop and recommended software
Raspberry Pi 5 Model B 4GB at stock speed (never overclock)

Never overclock your Pi.
Encourage optimization instead.