Powerconsumption and bandwith of expansion cards

Framework Laptop 13
1

Im thinking about, which extension cards should you get actually, if you want to have as little as possible power draw in:

idle (no cable pluged in) and,
used (cable pluged in)

And the second thing im interst in is, what is actually the bandwidth-difference, when used as display-connecter.

So first expansion cards im thinking about is USB-C vs DP and USB-C vs HDMI.

1a: Do i have the same bandwith when i use USB-C with DP adapter vs direct DP-expansion card? Would it maybe be possible to use a USB-C to displayport 2.0 or 2.1 adapter to get even more bandwith, than the native DP-expansion card? (which version is the dp expansion card (2nd gen) actually?)

1b: But what about power usage? Does the 2nd gen Displayport expansion card has less power draw in idle than an usb-c (withouth a USB-C to DP adapter connected) ? What about when a display is connected ? Which one does use less power (idle is more important for me) ?

2a: And same about HDMI: But there it is even more complicated, because the HDMI expansion card is only 2.0b but with an USB-C to HDMI 2.1 adapter you should be able to use HDMI 2.1 (so i don’t get the reason for a HDMI expansion card, if it is not HDMI 2.1). Or can you not use a HDMI 2.1?

2b: And also the power-question: Does the 3rd gen HDMI expansion card draws more power in idle? And does it use more, when a cable is plugged in (also idle is more important for me) ?

Is there actually somewhere information (like spec sheets) of the expansion cards and their powerdraw?

3: And then the question about ethernet expansion card: Do you think, an unused ethernet-expansion card does use more power than W-LAN ? And what do you think uses more power, when you use it ?

Extra question: Would it work, if you plug in the ethernet expansion card into a USB-C expansion card? I know this is stupid, but would it work for 1Gbit lan? Because when you don’t want to have the extra-width, you could just plug it out, when you leave home (because i guess you want to use W-LAN then). Therefore you could have an extra USB-C and would not have the extra-width, which the ethernet-card has.

2

Yes, because the DP expansion card is just a USB-C DP adapter in an expansion card case.

USB-C DP adapters mainly connect the DP wires. The speed that can be achieved is limited by the host. The only thing the adapter can do is to have not enough signal integrity for higher speeds to work. We won’t know that unless FW makes an official statement and some host device will actually support higher than HBR3 speeds (both AMD’s and Intel’s newest CPUs support faster speeds, but so far no device has come out that actually allows that to be used. Looks like it would require additional components on the board FW is not using).

Basically all upgraded / new cards seem to draw under 0.005W when idling / nothing is connected. That is what the new Gen 3 HDMI card can do and what my DP card does after upgrading the firmware to Gen 2. The Ethernet card as well
Edit:After a driver update I am only seeing 0.04W without ethernet plugged in and all power saving options manually activated. Maybe I mistook Amps for Watts or there is one special, older driver that consumes much less power in that situation…

Draw with displays connected should be identical as the new part was only the “unplugging” / sleeping when nothing is connected to the card.

When the ethernet card is plugged into network but the device is sleeping, even with additional driver options I only get it down to 0.3W. 0.7 if it is actually using 2.5G ethernet. But this does not work with default driver options. Then the card stuck to 0.7W draw permanently, even when sleeping.

Sure. All of them will. The USB-C expansion card is only a very short extension cable. And all other expansion cards are just normal USB-C devices that work in any USB-C port that supports whatever is needed (USB3, USB2, PD, DP, USB4).

3

Thanks for your answer.

So why then the gen2 of the dp expension card reduce its power draw? If it would have no effect, there could be now dp-specific powerreduction. Then it would mean, that the usb-c itself reduced it’s powerdraw. But that’s not the case. Its the specific expansion-card wird displayport.

Or was it hdmi which reduced its powerdraw? i dont know anymore, but doesnt matter. If it would have been always ~ the same powerdraw as a regular usb-c extension card, it would not be possible to lower power draw specific only on this type of expansion card.

What bandwith does USB 4 have in the Framework 16" Laptop? When i read on Wikipedia, there stays it have to be minimum 20GBit/s and maximum 40GBit/s. But there also stays since 2022 there is 80GBit/s possible.

So Im not sure now. What does the Framework 16" support? 20, 40 or 80 GBit/s ?

Depending on that it could support both, HDMI 2.1 and DP 2.1 or it could not (if only 40GBit/s).

4

As I understood framework, the main power savings are on the board, because the DP dongle kept parts of the board awake permanently, while now it acts like the DP adapter part is unplugged when nothing is plugged into the DP side, letting the board (or more precisely the TB retimers) sleep.

So in fact the DP card does not draw any more than 0.005W when active at full speed and it probably also did the same on previous firmware.
Note that I am measuring this with a simple USB-C Voltmeter. Might be imprecise and it might be that 0.005W is its floor.

The HDMI card actually has significant power draw itself when active (0.79W when driving 4K60), because it is actively receiving DP and converting it to HDMI. That is in addition to whatever the board draws because it senses a possible DP connection.
So the difference between old (0.074W idle, no monitor connected) to the gen 3 one (0.005W after a few seconds) will probably be small compared to the savings you get from the board itself.

The AMD CPUs used by FW are basically the same in the FW13 and FW16. They support 40G & 20G USB4, nothing more and as far as I know no feature of USB4 v2 at all.

DP speed is actually independent of USB4 speed. AMD has already claimed to support UHBR10 DP speeds on their last generation notebook CPUs, yet no device is actually listed to support this.
Intel for the 13th gen explicitly claims that the USB4 ports do support UHBR10 and UHBR20 (so basically the equivalents of 20G and 40G USB4 just with pure DP signal in only one direction), but it looks like the 13th gen FW does not actually make that available on its outputs.
But even Intel’s specs are unclear whether they can tunnel those new speeds through USB4 or only make those available directly. Since it is impossible to fit a full 4xUHBR10 connection through USB4 40G and anything slower would not be faster than previously possible DP connections and all existing USB4 hubs can at most extract HBR3 signals from USB4 tunnels tunneling them would probably not be worth it while being limited to 40G USB4.

USB4 does not tunnel HDMI. That has always been DP and any HDMI output from any USB-C or USB4 equipment is always an active DP-HDMI adapter. And yes those exist for the new FRL speeds. Maybe in the future they could even fit into an expansion card. But so far they have been buggy, especially with Intel iGPUs and so far there is no adapter available that does not strip VRR support, one of the 2 major reasons why you’d want a new HDMI port anyway.

1 Like
5

You say it supports 40gbps, not more. But you also say it probably support USB4 v2, which supports 80gbps. So What is it now :smiley: ?

My english is not that good: Does that mean, there is no HDMI adapter who support VRR ?

And what do you mean by wanting a new hdmi port? You mean the expansion card newest generation of hdmi 2.0b?

But it would also be a adapter, because its plugged in the usb-port. I dont understand you correctly. Could you say it in other words?

(Problem is also, the HDMI expansion card supports only 2.0b, which can not handle 4k 120Hz).

6

I misspelled, fixed now. It was supposed to be “no feature of v2 at all”.
But also: As with HDMI, DP, USB the spec version does not imply that specific new features are supported.
USB4 v2 includes other features. It would be completely valid that a device implements some of these new features without also supporting 80G speeds. That is why most people should never uses those version numbers and not trust anybody that is only giving such version numbers like “DP 1.4” and nothing else.

7

Right now you cannot get any DP-HDMI adapter that does the new FRL speeds (what many people call HDMI 2.1) and VRR. Fully utilizing those speeds is actually impossible with DP at only HBR3 speeds. That takes compression which causes a lot of bugs and complications, especially because most displays that need these newer speeds handle them very differently. The first generation of those DP HDMI adapters drew a lot of power and were big.
But basically every monitor that has “HDMI 2.1” ports that would benefit from any of the new features also does VRR.

I’d imagine there will be a DP-HDMI adapter in the future that does support FRL speeds etc. But it might be sensible to wait until those work more reliably, can handle VRR or DP has gotten fast enough so that it can be fully utilized.

8

I believe the bit you quoted and responded to here was addressing the bandwidth, not power draw, of the DP expansion card vs. a USB C (/Thunderbolt) expansion card with an external DP adapter. They should be the same because

From my understanding:

The 1st gen DP card has an issue with excess power draw. This was corrected in firmware in the 2nd gen DP cards (in conjunction with a BIOS/UEFI update) to bring it down to negligible levels. You can flash the new firmware onto a 1st gen card to make it functionally identical to a 2nd gen.

The 1st gen HDMI card also has an issue with excess power draw. Correcting it required a hardware modification to the card in addition to a firmware and UEFI fix. Framework sent 2nd Gen cards with early batches of the Intel 13th gen laptops for testing, and then made some further tweaks to create a 3rd gen. I don’t think we know whether the difference between 2nd and 3rd gen is hardware, firmware, or both. Framework also posted instructions for customers to perform their own hardware modification, which together with flashing the new firmware will essentially make the cars a 2nd gen.

9

Ok, so the bandwith is maximum at 40gbps and therefore it can’t reach HDMI 2.1 bandwith and for sure not the dp 2.1 bandwith.

That’s sad. This is a “not buy” reason for me, because i need 4k 120/144hz @ HDMI and 6k 144hz @ Displayport (two displays, but not at the same time). So i would need 1x HDM2.1 and 1x DP 2.1.

Hopefully the Framework 16" second gen will have USB4 v2 with fully 80GBit/s and hopefully it will be possible till then to buy a usb-c to hdmi 2.1 adapter with VRR support. I really need that and i know that’s difficult to find on laptops (sadly).

Ps: Yes, i know HDMI and USB does not force to use max. specs and that is horrible, But you know what i mean.

10

Again, DP speed and USB4 speed are independent of one another. Moreover the UHBR10 and UHBR20 speeds are actually the exact speeds that USB4 uses for 20G and 40G. That is why Intel says they support both, because they have already supported like 70% of what is necessary to reach those speeds. You won’t need USB4 80G unless you want to tunnel those DP connections through USB4.

And actually, no current 4K144 or 4K165 monitor uses any of the new DP speeds. They all use HBR3 speeds + DSC (both long defined in DP 1.4), which even the FW 13 11th gen could do.

Biggest limitation will be multi-monitor docking applications as a single monitor might already use up most of the available bandwidth. Which is sth. you have not asked for.

The new speeds will also be a mess at the start, as there are technical reasons to want to avoid UHBR13.5 like Intel is doing (at least on USB4 ports). And the first monitor I have seen that actually uses any of the speeds (Dell U3224KB - 6K) requires UHBR13.5 for uncompressed signals at full capabilities, precisely what is not supported by Intel. But thanks to DSC most people will never now. And existing iGPUs can already drive this by using only HBR3.

Same with HDMI. HDMI 2.1 added 6 new speeds. 1 is slower than old HDMI 18G TMDS. The next one is barely faster. Only the top speeds are actually faster than DP at HBR3 speeds. And since DSC has become popular and wide spread many monitors do not even support the top speeds of 40G and 48G but just use the lower speeds that DP can also already reach plus compression.
One of the reasons why just saying “HDMI 2.1” is near meaningless.

One additional point: GPUs already have internal resolution / refresh rate limits independent of the ports speeds and also total limits. Even the fastest Nvidia GPUs may go down to only 2 displays if they need to drive 4K165 and above instead of the default 4 displays.

While iGPUs can do a lot, driving those resolutions can take up a considerable amount of memory bandwidth that reduces performance (the difference between my iGPU needing to driving all my monitors vs just a single one at reduced refresh rate seems to be between 5 and 11GB/s in available memory bandwidth. And that is only 4K60, WQHD@60 & 3840x1600@120 all with 10 bit).

11

UHBR20 has 20GBit/s per lane and in total 80GBit/s. So that’s not true with the 40GBit/s. Source: DisplayPort - Wikipedia

And yes, 4k144hz does not need DP 2.1, but i was talking about HDMI 2.1. I need the full bandwith, what HDMI 2.1 can deliver and VRR for 4k120/144hz TV which today all have HDMI 2.1. And i need 6k120/144Hz for future upcoming (yes, not existing atm) Monitors on DP, therefore i need the full 80GBit/s of DP 2.1 and therefore i need the full 80GBit/s of USB4 v2.

I connect two monitors, but not at the same time. Always only one, so it’s not really a “multi-monitor” setup.

12

Both a DisplayPort Expansion Card and a USB-C with DP adapter can at best passthrough whatever the mainboard provides.

According to Framework’s knowledgebase: “[The DisplayPort Expansion Card] passes through DP Alt Mode directly from the Mainboard, enabling support for the maximum DisplayPort version and monitor resolution supported by the processor.”

The Intel processors that Framework offer advertise DisplayPort 1.4 support while the AMD processors include DisplayPort 2.1.

A USB-C expansion card is effectively like having no expansion card as far as the system is concerned (it’s just an extension), so you can’t beat that.

That being said, the 2nd gen DisplayPort card (which is the same as 1st gen with a software update) has low enough power consumption that I wouldn’t worry about it.

HDMI over USB-C is deprecated by the group that maintains the HDMI spec.

That means that most USB-C to HDMI adapters, such as the Framework HDMI expansion card, work by using DisplayPort over USB-C and then using an active adapter to translate the DisplayPort signal into an HDMI signal.

So far Framework has used Intel CPUs (AMD are just starting to be used), which are limited to DisplayPort 1.4. That means that if an adapter to get HDMI 2.1 was used it would still be limited to the much lower capabilities of the DisplayPort 1.4 being used upstream and wouldn’t get much benefit of being HDMI 2.1 instead of 2.0b.

Now that Framework is offering AMD CPUs with support for DisplayPort 2.1 I do wonder if they will release an updated HDMI card with support for HDMI 2.1.

At idle both the 2nd/3rd Gen HDMI and 2nd Gen DisplayPort Expansion Cards draw very little power.

Under load I’d expect the HDMI card to be worse (as it has the extra complexity of translating DisplayPort into HDMI).

13

Yes, but because it is unidirectional. USB4 40G just uses 2 of those links in each direction (= 40G in each direction). But on each wire, it is the same speed.

Like I said, meaningless by itself.

No. The 13th gen can actually use the new UHBR speeds added with DP 2.x. But apparently the USB4 retimers on the FW board do not support that (they would have to be the successors to the ones used in the 12th gen FW). Depending on what is used with the AMD notebook that limitation might be the same or not.

Edit: AMDs official specs for DP output from the 7040 iGPU:

image
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Intels official specs for DP output from the 13th gen iGPU:
image

None of that means any FW notebook can actually do that on its ports it is just what the iGPUs are limited to / supposedly be able to do (I have found no single device that actually supports any of that on a real port. Could be manufacturers being cheap or it actually not being available right now). For that you would need some spec from Framework promising that.

But that still would only be 38.7G of usable DP bandwidth, below the 42.6G HDMI tops out at currently and nowhere near the 77.5G of DP that Op wants.

The AMD dGPU of the FW16 is not going through expansion cards. But its dedicated USB-C port might actually support faster than UHBR10. But according to AMD the RX 7000 series is still limited to UHBR13.5.

Naming the HDMI & DP versions just obfuscates what the hardware actually supports.

14

But i did not read about USB4 is unidirectional compatibel. Or is it? For example USB4 v2 (when i remember correct) can use 120MBit/s unidirectional and 80MBit/s bidirectional. What i want to say: It’s not the double.

So yes, USB4 is as it seems 40GBit/s in bidirectional, but can it be used as 80MBit/s unidirectional (on version 1, not USB4 v2 which can do that anyway)?

15

The 120G mode is not unidirectional, its asymmetric. Its 120G down, 40G up (because 4 wire-pairs and each does 40G under Gen 4 speeds). And yes, I have not confirmed whether that asymmetric support will also be available for the old Gen 3 speed (so 60G down, 20G up), although I guess I could probably look that up in the USB4 specs…
Edit: I checked, USB4 spec says Gen 4 speeds only,

I already said that of course you cannot tunnel a DP40 connection through a 40G USB4 connection. All I meant was, that it would be perfectly normal for the port to support DP at UHBR20 speeds natively (so DP80, not tunneled through USB4) when it supports 40G USB4. And that is precisely what Intel is doing. You did not mention that you want that through a USB4 connection (for docking / single cable purposes), you specifically mentioned multiple connections for multiple displays and no dock or other peripherals, the opposite of a reason you’d need all of that tunneled through USB4.

16

But framework has no native displayport or hdmi as you said. So it’s clear it has to go over USB? Or what does tunneling mean?

And yeah, as i said i need one HDMI 2.1 and one DP 2.1. But i will not connect the display at the same time (as i said). So i don’t need the bandwith of them at the same time. Just one for the TV (HDMI) and one for a future Update of a Monitor (my next monitor shall be 5k or 6k with 120Hz).

And yes, you are right. I forgot that about the 120 and 40.

So but conclusion: Then USB4 v1 can not use 80MBit/s unidirectional and therefore it can not handle full HDMI 2.1 and UHBR20 bandwith? So independet of the frameworklaptop.

So it really would need the USB4 v2?

17

A USB4 port must support DP Alt mode, which is just plain old DP just on a different connector. Same as you could have mDP. It does not change that it is still DP signals. And the speed of that output is technically independent of any USB4 speed. You can access that with a simple USB-C to DP adapter. Or if your monitor where to support USB-C DP alt mode input, just with a USB-C cable directly.

Tunneled, means routing a DP connection through a USB4 connection. So for example you have a USB4 40G connection to some USB4 hub. You can then tunnel DP through that USB4 connection. The host will have to send DP data into the USB4 connection and the hub will unpack that and turn it into an actual DP signal, possibly on a DP connector again.
Intel’s 13th gen, according to the official specs already supports DP80 on all of its USB4 ports. You just cannot tunnel it (Intel does not say anything about not tunneling it at all, but it is obvious that it would not fit).

Now, FW has never claimed that the 13th gen FW supports that and in fact no other notebook with 13th gen CPU has, so that is probably not supported. But it is possible and independent of whether or not the USB4 ports support any USB4 v2 features, like the increased speed.

18

Ah ok, thank you. But the other question is, does that AMD too? Because 16" Laptop and the one 13" has AMD hardware. So do they support on their USB4 also 80GBit/s DP Alt mode ?

Were do you find these specific information ?