News DisplayPort 2.1 has a serious issue with UHBR-certified cables — Perhaps that's why Nvidia opted to stick with DP1.4 on the RTX 40-series

[Admin]

DisplayPort 2.1 is the most powerful video connection standard on the planet. But it has several issues that are seriously affecting its adoption.

DisplayPort 2.1 has a serious issue with UHBR-certified cables — Perhaps that's why Nvidia opted to stick with DP1.4 on the RTX 40-series : Read more

 

[Notton]

Me: What was so wrong with using 2 slower, longer, and uncompressed cables to hook up to the same monitor?

 

[Silas Sanchez]

DP is a disgusting standard. I wont tolerate my monitors disconnecting themselves when I press the power button off. Some truly awful designs.
After seeing 3 of my newer monitors all do this only with DP and thinking I had woken in the twilight zone, I went back to HDMI so my PC was actually usable.
Spent about 150bucks replacing the junk DP stuff with HDMI on my portable laptop setups. Forced to clean up after inconsiderate selfish people in this world.

 

[edzieba]

DP is a disgusting standard. I wont tolerate my monitors disconnecting themselves when I press the power button off. Some truly awful designs.
After seeing 3 of my newer monitors all do this only with DP and thinking I had woken in the twilight zone, I went back to HDMI so my PC was actually usable.
Spent about 150bucks replacing the junk DP stuff with HDMI on my portable laptop setups. Forced to clean up after inconsiderate selfish people in this world.

And vice-versa here. HDMI is for AV equipment, not PC equipment. Random switching to TV levels, fiddling with overscan defaulting to ON, demanding to become the primary audio endpoint (even when the monitor has no fscking speaker!), reporting incorrect EDID because the monitor decides it wants to boast TV-specs on the box and the host device dutifully assumes the monitor is not lying and sends it a HDR image it can;t dispaly properly, etc. Anything that isn't a TV is DP-only now unless there is absolutely no alternative, with far fewer headaches as a result. Over a 10,000 occupancy building (and another few tens of thousand elsewhere globally), the only time we have issues with monitor behaviour due to cabling is when we're stuck with HDMI for dual-function desks with a secondary device with no Type-C outputs, or someone has bent a connector trying to spin their screen 360 going from portrait to landscape.

At least it's not Dual-Link DVI anymore!

 

[wbfox]

DP is a disgusting standard. I wont tolerate my monitors disconnecting themselves when I press the power button off. Some truly awful designs.
After seeing 3 of my newer monitors all do this only with DP and thinking I had woken in the twilight zone, I went back to HDMI so my PC was actually usable.
Spent about 150bucks replacing the junk DP stuff with HDMI on my portable laptop setups. Forced to clean up after inconsiderate selfish people in this world.

Spent $150 on a cable?
Kinda funny that there are people that think the HDMI standards are any different, vendors can pretty much opt into or out of all of those neat features they advertise in HDMI standards, and not any good way to know because they will still qualify as a certified cable. DP, HDMI, USB, these are a few of the most horribly standardized things.

 

[LostFate]

It boggles my mind that shortening the max cable length to a forearm is an accepted solution instead of throwing an LC connector on the thing and just using multimode fiber. DisplayPort connectors aren't small so LC connector size is moot... Maybe I'm mistaken but I don't think DisplayPort needs to provide power over the cable (beyond sensing but you can sense a fiber link)... We are starting to push up against the limits of (reasonably long and thick) copper cables. We should probably just rip that bandaid off. TOSLINK became a thing in the 80s and was amazing straight through until HDMI took over with audio passthrough, without any major updates to the standard after inception. Time for fiber to take over for copper in the AV space again.

 

[truerock]

Here is a 10-foot, DisplayPort 2.1, UHBR20 cable (Amazons Choice):

UGREEN DisplayPort Cable 2.1 DP2.0 80Gbps Support 16K@60Hz 8K@240Hz 4K@240Hz HDR, HDCP, DSC 1.2a, Braided Display Port Cable Cord Compatible FreeSync G-Sync Video Card Monitor, 10FT​

So, it is not a physical limitation? The standards and certifications need to be updated?

 

[truerock]

It boggles my mind that shortening the max cable length to a forearm is an accepted solution instead of throwing an LC connector on the thing and just using multimode fiber. DisplayPort connectors aren't small so LC connector size is moot... Maybe I'm mistaken but I don't think DisplayPort needs to provide power over the cable (beyond sensing but you can sense a fiber link)... We are starting to push up against the limits of (reasonably long and thick) copper cables. We should probably just rip that bandaid off. TOSLINK became a thing in the 80s and was amazing straight through until HDMI took over with audio passthrough, without any major updates to the standard after inception. Time for fiber to take over for copper in the AV space again.

Wow! You have a 1-meter-long forearm?! You need to start pitching in MLB!

IMO... the reason that fiber-optic has not been successful for consumer electronics is that it has never been needed. And, I am reasonably certain the 10-foot long DP80 DisplayPort cables will be available as needed.
IMO

 

[DougMcC]

Here is a 10-foot, DisplayPort 2.1, UHBR20 cable (Amazons Choice):

UGREEN DisplayPort Cable 2.1 DP2.0 80Gbps Support 16K@60Hz 8K@240Hz 4K@240Hz HDR, HDCP, DSC 1.2a, Braided Display Port Cable Cord Compatible FreeSync G-Sync Video Card Monitor, 10FT​

So, it is not a physical limitation? The standards and certifications need to be updated?

UHBR20 vs UHBR80 is the issue though. I guess they are claiming 80G compatibility, but I notice that they very much don't make an UHBR80 claim explicitly. And their cable doesn't carry the 80 logo. Suspicious.

 

[LostFate]

Wow! You have a 1-meter-long forearm?! You need to start pitching in MLB!

IMO... the reason that fiber-optic has not been successful for consumer electronics is that it has never been needed. And, I am reasonably certain the 10-foot long DP80 DisplayPort cables will be available as needed.
IMO

If the standards body has set the advised maximum cable length to 1 meter and no one has been able to hit the bandwidth specs required over 2 (to say nothing of your 3 meter aspirations), then I'd say it's probably time to reconsider whether the move to fiber is needed or not. Sure, maybe they'll hit the 80 with copper... We have infiniband DACs cables that can hit higher than that at about that length. Not exactly flexible though, the shielding required to hit those bandwidths are pretty intense. On the flip side; 10 feet of LC-LC MMF is about 7 dollars, weighs as much as a couple pieces of paper, is significantly more flexible...

 

[truerock]

UHBR20 vs UHBR80 is the issue though. I guess they are claiming 80G compatibility, but I notice that they very much don't make an UHBR80 claim explicitly. And their cable doesn't carry the 80 logo. Suspicious.

It is confusing...

There is UHBR10 which requires a DP40 cable for 40 Gb/sec, and
UHBR20 which requires a DP80 cable for 80 Gb/sec

There is no UHBR80

 

[truerock]

If the standards body has set the advised maximum cable length to 1 meter and no one has been able to hit the bandwidth specs required over 2 (to say nothing of your 3 meter aspirations), then I'd say it's probably time to reconsider whether the move to fiber is needed or not. Sure, maybe they'll hit the 80 with copper... We have infiniband DACs cables that can hit higher than that at about that length. Not exactly flexible though, the shielding required to hit those bandwidths are pretty intense. On the flip side; 10 feet of LC-LC MMF is about 7 dollars, weighs as much as a couple pieces of paper, is significantly more flexible...

Again, I don't think there is anything limiting DP80 cables from being 6-feet or 10-feet long. I think the issue is that there isn't sufficient demand for longer cables at this point in time. I don't know.
I am reasonably certain there will be 6-foot long Vesa certified DP80 cables available this year. We will see.

Fiber-optic cables for consumer, short distances is just not getting any traction for a number of reasons. I do not think DP80 is going to change that. Before 2025, I think that will be obvious - IMO.

Fiber-optic is the preferred solution for commercial super-high-bandwidth, very long-distance cables.

 

[LostFate]

Again, I don't think there is anything limiting DP80 cables from being 6-feet or 10-feet long. I think the issue is that there isn't sufficient demand for longer cables at this point in time. I don't know.
I am reasonably certain there will be 6-foot long Vesa certified DP80 cables available this year. We will see.

Fiber-optic cables for consumer, short distances is just not getting any traction for a number of reasons. I do not think DP80 is going to change that. Before 2025, I think that will be obvious - IMO.

Fiber-optic is the preferred solution for commercial super-high-bandwidth, very long-distance cables.

You wouldn't classify 80gbps as super high bandwidth? No one is asking for cables over 3 feet long?

I don't believe the lack of fiber in the ever increasingly bandwidth hungry AV space is due to lack of demand caused by a lack of benefit. I can maybe see a lack of demand based on lack of knowledge but the standards body is aware of fiber and it's capabilities, they are the ones making the recommendations and they could just as soon say "hey, this is getting untenable, something needs to change". The people on the standards committee that make and supply cables want to squeeze customers, so they won't settle on an existing connector attached to a commodity transmission medium. An argument can be made for retaining backwards compatibility but the market is so saturated with deceptive products at this point that they'd be better off making a clean break on the transmission medium and just continue to maintain the protocol. It's not unprecedented, we have DisplayPort over USB-C.

Again, I can get 100 foot LC-LC MMF cable that will do 100gbps for about 30$ (or less). I can get a 10 foot cable for about 7$ that will do the same. The primary issue isn't hyper long lengths, it's a stable bandwidth over a given length; something fiber excels at from short to long lengths and something copper only barely manages to be passable at (at the bandwidths we are talking about) in what ought to be considered remarkably short lengths. Like copper traces on a PCB for newer gen PCIe lanes; more bandwidth = higher frequency = more shielding/active signal regeneration/shorter paths (pick at least 1)... Shoving more bits down copper is an increasingly expensive losing proposition. Fiber is cheaper and more forward thinking. Used to be too expensive, now it's ubiquitous in so many places the economies of scale make it more viable than forcing copper.

 

[TJ Hooker]

Here is a 10-foot, DisplayPort 2.1, UHBR20 cable (Amazons Choice):

UGREEN DisplayPort Cable 2.1 DP2.0 80Gbps Support 16K@60Hz 8K@240Hz 4K@240Hz HDR, HDCP, DSC 1.2a, Braided Display Port Cable Cord Compatible FreeSync G-Sync Video Card Monitor, 10FT​

So, it is not a physical limitation? The standards and certifications need to be updated?

I question how reliable that cable will actually be at 80 Gbps. Keep in mind that many of the positive reviews are likely coming people who aren't actually running at high enough resolution/refresh rate to max out the bandwidth. And there's no way to know which reviews apply to which cable length (as Amazon just combines them all into a single rating). Plus the usual fake/astroturfed reviews.

 

[thestryker]

This problem seems entirely caused by VESA not considering cable length with UHBR20 bandwidth. They should have already had an active cable specification done at the very least if not a completely different spec using fiber for the top choice.

And vice-versa here. HDMI is for AV equipment, not PC equipment. Random switching to TV levels, fiddling with overscan defaulting to ON, demanding to become the primary audio endpoint (even when the monitor has no fscking speaker!), reporting incorrect EDID because the monitor decides it wants to boast TV-specs on the box and the host device dutifully assumes the monitor is not lying and sends it a HDR image it can;t dispaly properly, etc. Anything that isn't a TV is DP-only now unless there is absolutely no alternative, with far fewer headaches as a result. Over a 10,000 occupancy building (and another few tens of thousand elsewhere globally), the only time we have issues with monitor behaviour due to cabling is when we're stuck with HDMI for dual-function desks with a secondary device with no Type-C outputs, or someone has bent a connector trying to spin their screen 360 going from portrait to landscape.

At least it's not Dual-Link DVI anymore!

Spent $150 on a cable?
Kinda funny that there are people that think the HDMI standards are any different, vendors can pretty much opt into or out of all of those neat features they advertise in HDMI standards, and not any good way to know because they will still qualify as a certified cable. DP, HDMI, USB, these are a few of the most horribly standardized things.

I think what that poster was referring to is that when you're using multiple screens (at least on Windows) turning off a monitor connected by DP will disconnect the monitor from Windows entirely which can mess with scaling and window locations. This does not happen at all when connected via HDMI (and yes I mean at all, even using DP to HDMI adapter or even the same screen with DP vs HDMI).

 

[watzupken]

The title feels like it’s helping Nvidia to find an excuse not to adopt a newer DP standard. Ironically, Nvidia chose to adopt a power connector that melts.

 

[Eliad Buchnik]

I question how reliable that cable will actually be at 80 Gbps. Keep in mind that many of the positive reviews are likely coming people who aren't actually running at high enough resolution/refresh rate to max out the bandwidth. And there's no way to know which reviews apply to which cable length (as Amazon just combines them all into a single rating). Plus the usual fake/astroturfed reviews.

It's not 80Gbps (at least not certified) and VESA should be holding them liable for false advertise.
you can see at VESA website: https://www.displayport.org/product-category/cables-adaptors/?ps=ugreen
It's just 40Gbps cable. Also keep in mind about reviews in Amazon
1) the only cards that support 80Gbps currently are some professional cards from AMD : the PRO W7800 and PRO W7900 cards, not many people have them (regular 7000 series support only UHBR 13.5)
2) not many monitors support 80Gbps at the first place, I know only about Gigabyte FO32U2P
3) people will end up using DSC one way or another for their monitors.
currently the longest certified cable I've seen is 1.2m. I think there is no escaping from active cables,
like with TB 4 and the use of Linear Redrivers, and even then they stretch to length of 3m for copper cables (longest one i've seen is an Apple one), and if will need even longer cables those would probably be optical ones, and if corning TB3 optical cable are something to relay on - you will pay server grade networking cable price for them .