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It's not the connector, it's the communication protocol.

It's super lame though. It will be great to watch the downfall of HDMI Forum when their artificial dam against DisplayPort in the living room finally breaks.





What is the dam against DisplayPort anyway? I never see it on TVs for whatever reason.

Actually it’s a bit odd, in my mind DisplayPort is highly associated with quality. But I don’t actually know if it is the superior connector or if it just seems that way because monitors are usually better than TVs in every metric other than size and brightness.


HDMI Forum don't like TV SOC boards that have both kinds of ports and discourage them from being made.

Also, HDMI Forum don't like converter boards that support every advanced feature at once (Variable Refresh Rate, HDR, etc.) and won't license them.

DisplayPort and HDMI kind of leapfrog each other in terms of technical superiority, so neither is definitively technically superior in the long term.


Mass-market compatibility.

It's already difficult to find TVs with four fully-compliant HDMI ports; often you'll get a TV with one HDMI 2.1 port and three HDMI 2.0 ports, and sometimes the 2.1 port will also be the only eARC port so you have to choose between high framerates/resolutions and using a sound bar. In other words, even with just HDMI getting a decent set of ports is difficult.

The idea of TV manufacturers also adding DisplayPort ports seems ludicrous to me - not because it's a bad idea, but because I can't imagine them going to the trouble if there's no tangible demand. At best I could see them replacing HDMI ports with DP ports because there's limited space on the motherboard, but that would still require the board to have both HDMI and DP circuitry/chipsets and HDMI/DP certification/testing.

Then you have a TV with, say, two HDMI ports and two DP ports - which, for most users, means "two ports" since 99% of people don't have any hardware they want to connect to their TV that supports DP anyway.

So basically unless we start seeing game consoles, AppleTVs, and Rokus supporting DisplayPort we won't see TVs supporting DisplayPort, and we won't see any of those devices supporting DP because they don't need to - HDMI works fine for them and it's sufficiently universal.

Maybe China's new HDMI replacement will take off over there and make its way into devices over here, but I'm not holding out hope.


My understanding is that the HDMI 2.1 port situation on TVs is, weirdly enough, a SoC limitation from a single vendor.

Almost everyone (apart from... Samsung and LG, IIRC) is using MediaTek SoC for the brains for the TVs, and they just seem to be unable to make one that has enough bandwidth for 4xHDMI 2.1.

AFAIK LG and Samsung still handle theirs in-house (and that's why LG was the very first "big" vendor to ship 2.1 at all, and they rolled it out to all four ports even on their midrange TV's in _2019_!); and it's common to see those brands have more 2.1 ports.

This should be getting better in 2025/2026 model years, since it seems MediaTek has finally managed to ship a SoC that does it; but it's ridiculous how long it's taken.


China's new HDMI replacement currently has no known benefit over HDMI in terms of protocol governance issues.

You're right. I should have said 'maybe China's new HDMI replacement will be managed better and take off'.

Apparently, the Hisense U8QG has DP-over-USB-C support. This might be the Trojan horse for DP in the living room.

The supported version of DisplayPort in that TV is on par (-ish) with HDMI 2.0; and not enough for HDR 4k120; which is one of the selling points of HDMI2.1.

Many TV manufacturers are part of the HDMI forum...

https://hdmiforum.org/members/


Here's a stupid question: per the site, "any entity wishing to make an active and material contribution to the development of future HDMI Specifications" can join the HDMI Forum for $15,000 p.a., and the Board of Directors is elected by majority vote by members.

Is there anything other than the money and desire to do so stopping 100 well-heeled Linux users from joining up and packing the board with open source-friendly directors who would as their first official act grant AMD permission to release its driver?


This sounds like what microsoft did to get their Office formats standardised by ISO. Paid membership to a bunch of folk and had the vote in favour of approving the standard. (I'm summarising *a lot*, but that's the general gist of it).

You’d want to submarine it because the forum could change its rules in “defense”.

But yes, it wouldn’t be much to do.


Sounds like a conflict of interest

DRM, I believe

I don't think so, DisplayPort incorporates the same HDCP encryption standard that HDMI uses.

edit: the source that I found was incorrect, and this statement is false.

DRM is optional with DisplayPort but mandatory with HDMI.


Did that change in a more recent version? According to the (admittedly old) source linked from the Wikipedia article, integrators are allowed to skip HDCP but incentivized with reduced royalties if they do support it.

https://web.archive.org/web/20081218170701/http://www.hdmi.o...

> For each end-user Licensed Product, fifteen cents (US$0.15) per unit sold.

> If the Adopter reasonably uses the HDMI logo on the product and promotional materials, then the rate drops to five cents (US$0.05) per unit sold.

> If the Adopter implements HDCP content protection as set forth in the HDMI Specification, then the royalty rate is further reduced by one cent (US$0.01) per unit sold, for a lowest rate of four cents (US$0.04) per unit.


You're right, the source that I found was incorrect.

> It's not the connector, it's the communication protocol

In particular the link training procedures needed to reliably push 48 Gbit/s over copper are probably very non-trivial, and could be considered "secret sauce".


That's done by the PHY layer, there's no need to implement that in software.

tbh it'll probably be GPMI, not DisplayPort

GPMI isn't an open standard and it doesn't support HDCP. It might end up being very popular in China but it will be a hard sell in markets that aren't primarily consuming Chinese media.

Why would display port ever start taking over in the living room?

It's cheaper to implement than HDMI. So if DisplayPort ports are common on displays, devices will start using it (cheapo devices first). If DisplayPort ports are common on devices, displays won't need HDMI anymore. Plus, industry-wide, it's wildly inefficient to have one high-bandwidth video connector for monitors and a different one for TV's when the technical distinction between those is pretty much non-existent and we could scale our engineering effort across a much wider set of devices.

So, after a transition period, cost-saving will eventually lead to DisplayPort taking over.


> when the technical distinction between those is pretty much non-existent

I think CEC support is still spotty and ARC (audio return channel) isn't supported at all in DP.


Well, CEC is a huge mess and barely works[1]. You're right on ARC and eARC. I'd rather DP had a better version of both, but that wouldn't happen.

[1]: If you have a stack that works, I'm happy for you, but trust you're just lucky to have a working combination.


Because the manufactures don't have to pay a license fee and so once someone start using it everyone will follow and then drop hdmi. However so far nobody has cared enough to be first.

USB C is at least one reason that will apply constant pressure.

Well, if this were a free market, b/c there would be demand for it? I want a more standardized protocol so I need less cabling and connectors, and I want features like 4k that HDMI effectively (see TFA) does not support.

I would vote with my wallet … if I could.

Like, why do we need two connectors, for the same thing? DP is clearly technically superior.

Of course, there's a wide range of issues: there's a number of comments on this article stating how the HDMI forum is manipulating the market (e.g., by suppressing competitor connectors on the board, offering lower royalties for bugs, suppressing specifications), and then there's just getting out-competed by the litany of consumers who have no idea and do not care to know what they are buying, and marketplaces like Amazon that promote mystery-meat wares.




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