What exactly does "Higher power consumption" for expansion 1 and 3 mean?

If there is a device connected the whole point is kinda moot since the port needs to stay on anyway. Not being able to sleep when nothing is connected isn’t really a problem if something is connected and you aren’t supposed to sleep anyway.

Usb-c isn’t powered by default, usb-a is.

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I don’t think that’s really the issue. Otherwise, it would just be an unavoidable problem. It would exist on Intel board as well. And also Framework wouldn’t be looking for an AMD compatible retimer without the issue.

Retimers are about signal integrity at high frequencies. They receive signals, understand them, and then re-emit them – at high frequencies, traces running the (halfish?) length of a motherboard are long enough for signal degredation (somebody correct me if I’ve got the wrong idea). They weren’t needed with the comparatively lower speeds of USB 2, but they are needed for Thunderbolt / USB-4… not sure about USB 3 stuff, not that it’s particularly relevant here (only learned retimers existed while reading about Framework laptop power drain during sleep).

There’s been this longstanding issue where some of the expansion cards consume disproportionate amounts of power, especially while the laptop’s asleep, even when they’re empty. USB-A expansion cards keep the retimers awake I guess, or something like that, and they use enough power to be noticeable. That’s what this is about. I don’t know, but doubt that there’s a big difference among expansion cards if you’re actively using the port or have something else plugged into it, aside from the power requirements that you’d expect.

This problem does exist on Intel motherboards.

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Last I read about it, they said they had a fix. Though it might be buggy.

I’d be really interested to learn more if you know of any fixes for the combination of

  • 11th gen Intel CPU
  • USB-A expansion card
  • laptop in a suspended state

I have seen Framework make progress on a number of other expansion card power usage issues, but not mine. It’s always possible I missed something.

And in a subsequent reply, he seems to confirm that it’s part of BIOS updates for all intel generations.

I don’t know if it applies to the USB-A issue, but for some issues where a few people still have problems when it’s supposed to be fixed, I think I recall mention that it could be due to component tolerance on the particular mainboard. Not that a part is “defective” / out of tolerance, but further from the target than most.

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So this is only about putting the ports to sleep when nothing is connected, and not about higher power consumption when something is connected? No one mentioned that before, interesting.
If so, related question: Would it be more power-efficient to connect devices (especially ones that don’t need USB4 which, let’s be honest, currently is the absolute majority of devices) to expansion ports 2 and 4, or do they need as much power as 1 and 3 when active?

And I don’t know if Intel laptops are affected, but I think only the specs pages of AMD laptops mention “Higher power consumption” for some ports.

It has been mentioned before in older threads.
The source of the problem is that in the USB-A adapter the USB-C port pin that causes the CPU to turn on power to the port is permanently grounded in the USB-A adapter, as there is no other way to get the insertion of a USB device into the adapter to make the USB-C port on the laptop turn on power.

If you go digging back in previous threads there is quite a discussion about the problem, and someone was looking into modifying the USB-A adapter by fitting a microswitch that is physically operated by plugging in a USB device to ground the line from the USB-C power on pin instead of having it permanently grounded. IIRC FW were quite interested in what he was trying to do, but I don’t know if they were actually looking at doing a production version of the modification.

yes

When active there should not be a difference

The redrivers on the intel boards are apparently able to sleep with an usb-a module inserted (as they should but the amd ones are unfortunately bugged in that reguard)

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Thank you very much for all the replies and clarifications!

Framework should make a FAQ entry or something about this and link it on the spec pages as reference for that higher power consumption note, so the next person who wonders about it finds the information more easily :slight_smile:

I am on BIOS 3.17, 11th gen Intel, can confirm it’s not fixed, at least on my hardware. There probably was more than one power usage issue, though…

Just came across [RESPONDED] AMD Batch 1 Guild - #123 by Zachary_Burnett which has a copy of an email sent out to AMD pre-orderers describing the issue as increased power usage with those ports either empty with USB-A, or populated with USB 2 devices, as opposed to USB 3. So this is probably not exactly the same as my laptop’s sleep issue. Sorry for the confusion. (It’d be nice if there was a “state of power usage by motherboard and expansion card” knowledgebase article someplace…)

Down that thread a bit, nrp says that the Intel issue is fixed in 13th gen boards, but 11th and 12th gen still have edge cases: [RESPONDED] AMD Batch 1 Guild - #156 by nrp

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Interesting - so apparently the issue is a bit more complex than

(because an empty USB-A adapter has high power draw, and so does a USB2 device connected to it, but an USB-A adapter with a connected USB3 device doesn’t)

So I guess my question about connecting USB2 or USB3 devices to those ports with a USB-C cable is still relevant and unanswered

If something is plugged in there is no difference. That is the answer to that question.

So why does a connected USB2 device (or no connected device) create high power draw, but a connected USB3 device doesn’t?
Why is it different if a USB2 device is connected directly with a USB-C cable?

Also, the port does not need to stay on when the laptop is in suspend mode, I think?

If anything, usb2 or 3 or displayport alt mode or usb4 with pcie tunneling or whatever else you can pump over the port is active there is no extra power draw as it is active. There is extra power draw when nothing is plugged in because the usb-a expansion card prevents the redriver from sleeping right (cause the redrivers are bugged) when nothing is plugged in.

The problem is extra power use when not in use, when in use it doesn’t matter as is is in use.

It doesn’t need to but the usb4 re-drivers definitely seem to have problems actually doing that.

Ok, so, on the affected expansion ports:

  • When the laptop is running:
    • having an empty USB-A adapter plugged in does draw extra power, because the redriver (retimer?) doesn’t sleep right
    • having a USB-A adapter with any kind of USB-device connected also draws power, but only as much as one would expect from a USB-device being active?
    • empty USB-C adapters do not draw extra power
    • USB-C adapters with any kind of USB-device connected also draw power, but only as much as one would expect from a USB-device being active
  • When the laptop is in suspend mode:
    • having an empty USB-A adapter plugged in still does draws extra power, because the USB4 redrivers (retimers?) screw up even when they should be sleeping
      (ok, to be fair, there is this whole “wake computer by pressing key on USB keyboard” nonsense that might require USB-ports to be at least half-awake)
    • having a USB3 device connected via USB-A adapter does not draw extra power (according to [RESPONDED] AMD Batch 1 Guild - #123 by Zachary_Burnett)
    • having a USB2 device connected via USB-A adapter does draw extra power
      • what about USB1.2 ? (still relevant for input devices, I think?)
      • why does it make a difference if it’s a USB2 vs USB3 device?
    • empty USB-C adapters still don’t draw extra power (of course)
    • Any kind of USB-device (USB1 - USB4) connected through a USB-C adapter presumably does not draw extra power

(I hope I’m not being too annoying, I just want to understand wtf is going on exactly :))

yes

plus the power the redriver an all that uses yes

jup

yes

I haven’t looked into sleep much as I don’t use it but let’s see what I can answer there

USB 1, 1.1, 1.2 and 2 use the same pins and physical interface and are usually handled together so I’d expct thm to behav the same.

That is probably because usb2 (+ 1 and co) and usb3 are entirely separate interfaces, though usb3 is required to have a usb2 interface taped to it. If you look into an usb3 port you can see the front 4 pins, the outer pins are 5v and gnd and the middle pins are the usb2 data lines, then in the back there are the 2 usb3 pairs and a signal gnd, the only thing the 2 interfaces share is power. You can actually use both at the same time even if the spec at least frown upon that, laptops sometimes do that internally when they run out of ports for smartcard readers and fingerprint and stuff.

I find that bit quite funny, “How do we make our new interface backwards compatible? Just tape the old one onto it” XD

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I disassembled the USB-C and USB-A and they are just extension cables, you can plug a USB-C device directly onto the mainboard. How does an empty USB-A draws current? I found that the top surface on the USB-C expansion card is plastic while the top surface of the USB-A is metal, does that affects grounding? What will happen if I swap the top serface i.e putting the USB-C expansion card cover into a USB-A expansion card?

EDIT: Where can I find Expansion Card Functionality on (11/12/13th Gen Intel® Core™)? There is only an Expansion Card Functionality on Framework Laptop 13 (AMD Ryzen™ 7040 Series)

A USB-A card needs to tell the USB-C controller that it’s present so that the controller falls back to compatibility. It does this through a resistor on the CC line. Unfortunately, this causes the AMD compatible retimers to be unable to sleep.

Metal was used for the USB-A card only due to being thinner, needed to accommodate the USB-A port height.

All slots are supposed to be the same on the Intel boards.

See my explanation in post 10 of this thread for the reason it causes unexpected current draw.

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