GPU-Z Display port bandwidth - Is it accurate?

[Mussels]

Just got a new monitor that supports DP 1.2, 1.3 and 1.4 vs the old 1.2 and i'm seeing the exact same readings
Wondering if GPU-Z could be incorrect, or if I've been ripped off by a shoddy cable from amazon that claims to be 1.4, but is not

5.4 x4 = 21.6, which matches the DP 1.2 standard

DP specs also include clock rates, so it's hard to tell what DP version this is running at without seeing those clock rates or HBR versions listed

So would this be a software thing, or another amazon special cable? It's difficult to move this display closer to the PC to test with my other, shorter cables

 

[Logan7]

Doesn't answer the question but just for what it's worth, with AMD graphics cards the link speed is reported in the driver software. So maybe GPU-Z is just reporting what the driver says.

 

[Mussels]

This is the display
32” Class UHD 4K Monitor | 32UK550-B | LG Australia


Has OSD options for DP 1.1/1.2/1.3/1.4

And this cable (Which I accept may be falsely advertised as higher spec than it really is)

It's just not reporting values higher than 1.2 can achieve and i want to overclock the tits out of it, but it's giving poorer results than my inferior DP 1.2 monitor next to it (68Hz vs 70Hz before it's out of bandwidth)

Oh here we go, LG had a driver for the monitor which renamed it from generic "LG HDR 4K" to "LG electronics LG HDR 4K"
CRU sees it as something else yet again

Can't seen anything ELSE that it changed, but good to know it did something...

Found someone with the exact same issue from 2020
MPG341CQRV and Displayport 1.4 | Overclock.net

Is it because the link is still 5.4Gb, but with compression so GPU-Z cant report the higher speed link?



Edit: The driver unlocked 4K with 10 bit color in the nvidia CP
Will investigate anything else it changed

Edit 2: The driver installed *something* but i still had to manually update the monitors driver directly

The monitors UI does have some effect
DP 1.1 locks me right down

The monitor shows as a GSM774F on HDMI and a GSM7750 on DP
I've never seen a monitor do THAT before
Using CRU the displayport and HDMI timings are very, very different on this display. That's weird.
(DP on left, with lower MHZ)

Tried another DP cable this one rated for 8K, same result - bandwidth doesn't go past DP 1.2 settings

Lotta information here that doesn't help my issue whatsoever, lol.

For example:

My HDMI 1.2 display has a single HDMI 2.0 port, and using a DP 1.4 to HDMI 2.0 adaptor, i see the higher link speeds

It also gives a blank image at 60Hz and only works at 59.97Hz which makes it fun when 60Hz is the default

Just spent $60 on local-store, verified good 8k 60Hz DP1.4 cables and... no change
rude monitor is rude.

Why offer DP 1.4 if it doesnt get used?!?

 

[W1zzard]

Are you actually running a resolution/refresh rate that requires the higher link speed?

 

[thewan]

Just got a new monitor that supports DP 1.2, 1.3 and 1.4 vs the old 1.2 and i'm seeing the exact same readings
Wondering if GPU-Z could be incorrect, or if I've been ripped off by a shoddy cable from amazon that claims to be 1.4, but is not

5.4 x4 = 21.6, which matches the DP 1.2 standard

Within the DisplayPort standard are transmission modes. Newer versions of DP support newer transmission modes.

The monitor and the gpu uses the DP 1.4 standard, it doesn't mean it needs to use the best transmission mode within that standard. If a lower transmission mode is good enough for the resolution and refresh rate the monitor is using, it doesn't need anything more.

Your monitor only goes up to 4k60, which only requires HBR2 for both 8bit and 10bit. Which means GPU-Z is reporting the correct Transmission Mode your monitor and GPU is communicating with. HBR2 is 5.4Gbits per lane. DP 1.4 supports all transmission modes up to HBR 3. What is wrong with it running at a lower transmission mode if its not necessary to run higher?

 

[kiriakost]

Interesting topic.

I do thoughts about a new 24" IPS 165Hz, the one of my likes, this is technology 15 Aug 2022 and has display port DP 1.2

When my GTX1060 6GB (Jul 2016), this supports up to DP 1.4 = HBR3 = 4K at 100 FPS
Its good to be aware, that I will never feel bandwidth-limited with this card.

 

[P4-630]

When my GTX1060 6GB (Jul 2016), this supports up to DP 1.4 = HBR3 = 4K at 100 FPS
Its good to be aware, that I will never feel bandwidth-limited with this card.

You're all good with point and click games at 4K with that GPU...

 

[kiriakost]

You're all good with point and click games at 4K with that GPU...

I bet that you are talking due personal experience, RTX 2070 with stripped DLSS cores = GTX 1060

 

[P4-630]

I bet that you are talking due personal experience, RTX 2070 with stripped DLSS cores = GTX 1060

I don't have a "RTX 2070", nor a 4K monitor...

 

[kiriakost]

I don't have a "RTX 2070", nor a 4K monitor...

Use this opportunity, so to upgrade your forum profile.

 

[Mussels]

Interesting topic.

I do thoughts about a new 24" IPS 165Hz, the one of my likes, this is technology 15 Aug 2022 and has display port DP 1.2

When my GTX1060 6GB (Jul 2016), this supports up to DP 1.4 = HBR3 = 4K at 100 FPS
Its good to be aware, that I will never feel bandwidth-limited with this card.

GTX 1060 only has DP 1.2, it's 1.3/1.4 "Compatible"

There is a firmware update for these GPU's but it's more about making them compatible, it does not add the new features and speeds
Graphics Firmware Update for DisplayPort 1.3 and 1.4 Displays | NVIDIA (custhelp.com)


This seems to be the issue with my DP "1.4" display as it doesnt use HBR3 or DSC at all, but may support one of the other features like more audio channels


As this goes back to my original question of if GPU-Z was inaccurate or my monitor dishonest, i'm going to say that when i've tried three brands and four VESA certified "8K" cables, the monitor is the problem

DP 1.4 enables a higher compression mode - that may not be supported or used - new audio standards, and in theory uses less bandwidth for the same settings



Heres my 65Hz 10 bit settings and the link rate GPU-Z reports at DP 1.4

and then changed to DP 1.2...

The only difference seems to be on DP 1.2 certain brightness settings cause flickering and they dont on 1.4
I Cant explain how THAT works, but clearly something saying its DP1.4 compatible does NOT mean HBR3 is supported



HBR 3 with DSC seems to rely on supporting the " YCoCg color space" instead of RGB, which i guess we dont have.



Edit: Ahah

DP 1.4 is required to enable HDR - even if they don't support the VESA standards or do it poorly, so you'll get extremely limited DP 1.4 support just so they can accept a HDR signal

And here we go with an active DP to HDMI cable, which is showing HBR3 as supported but not active - but enables 12 bit colour

Pity it's a bit too SHORT for me to use normally, but it's interesting how this is behaving even it's a monitor issue

DP to DP
4K 10 bit

HDMI to HDMI
4k 8 bit

DP to HDMI:
4k 12 bit

THIS MAKES NO SENSE.

 

[kiriakost]

GTX 1060 only has DP 1.2, it's 1.3/1.4 "Compatible"
View attachment 278542

There is a firmware update for these GPU's but it's more about making them compatible, it does not add the new features and speeds
Graphics Firmware Update for DisplayPort 1.3 and 1.4 Displays | NVIDIA (custhelp.com)


The only difference seems to be on DP 1.2 certain brightness settings cause flickering and they dont on 1.4
I Cant explain how THAT works, but clearly something saying its DP1.4 compatible does NOT mean HBR3 is supported

HBR 3 with DSC seems to rely on supporting the " YCoCg color space" instead of RGB, which i guess we dont have.

DP 1.4 is required to enable HDR - even if they don't support the VESA standards or do it poorly, so you'll get extremely limited DP 1.4 support just so they can accept a HDR signal

And here we go with an active DP to HDMI cable, which is showing HBR3 as supported but not active - but enables 12 bit colour

Pity it's a bit too SHORT for me to use normally, but it's interesting how this is behaving even it's a monitor issue

DP to DP
4K 10 bit

HDMI to HDMI
4k 8 bit

DP to HDMI:
4k 12 bit

THIS MAKES NO SENSE.

GTX_1060_User_Guide.pdf this is documentation of 7/2016
I have my copy downloaded since 12/2021
NVIDIA it clearly mention DP as the No1 recommendation for primary display.
My GTX1060 latest revision, this came with the latest DP firmware, and the NVIDIA updater tool, always report that I am updated, even their latest version.

I will leave out of the equation any DP to HDMI gadgets.

Everything makes sense if you examine latest Fast IPS screens and their specifications according to their dimensions.
Even the latest 23~24" they do not require anything higher than DP 1.2
In conclusion, higher than DP 1.2 this is there to serve the very few and huge in dimensions computer screens.

 

[Mussels]

GTX_1060_User_Guide.pdf this is documentation of 7/2016
I have my copy downloaded since 12/2021
NVIDIA it clearly mention DP as the No1 recommendation for primary display.
My GTX1060 latest revision, this came with the latest DP firmware, and the NVIDIA updater tool, always report that I am updated, even their latest version.

I will leave out of the equation any DP to HDMI gadgets.

Everything makes sense if you examine latest Fast IPS screens and their specifications according to their dimensions.
Even the latest 23~24" they do not require anything higher than DP 1.2
In conclusion, higher than DP 1.2 this is there to serve the very few and huge in dimensions computer screens.

okay so

1. That has nothing to do with this thread i created to sort out my monitor issue
2. You're posting a lot of random mismatched facts. Fast IPS? That's a backlight technology.

Displayport technology has NOTHING to do with monitor size. Ever.
Please don't make up a list of facts yourself, and then make a conclusion based on them.

 

[kiriakost]

okay so

1. That has nothing to do with this thread i created to sort out my monitor issue
2. You're posting a lot of random mismatched facts. Fast IPS? That's a backlight technology.

Displayport technology has NOTHING to do with monitor size. Ever.
Please don't make up a list of facts yourself, and then make a conclusion based on them.

You are the last person on the planet earth, that you will advice me of how proper scientific research this is executed.
24" screens does not require any HUGE bandwidth, DP 1.4 this is sufficient.

 

[Mussels]

You are the last person on the planet earth, that you will advice me of how proper scientific research this is executed.
24" screens does not require any HUGE bandwidth, DP 1.4 this is sufficient.

What has any of this got to do with the thread here?



Let me summarise what you've stated so far, and then i'll ask you again how it's relevant to this thread i created and the question I asked

I do thoughts about a new 24" IPS 165Hz, the one of my likes, this is technology 15 Aug 2022 and has display port DP 1.2

When my GTX1060 6GB (Jul 2016), this supports up to DP 1.4 = HBR3 = 4K at 100 FPS
Its good to be aware, that I will never feel bandwidth-limited with this card.

*Your Graphics card supports DP 1.4
False. It supports DP 1.2 but is 1.4 compatible - meaning it displays a signal on them, but is 100% limited to DP 1.2 speeds and HBR2 mode
There was a BIOS update for them to make them 1.4 compatible because they gave a black screen on DP 1.3 and 1.4 displays. The only thing this adds is HDR support.

165Hz means nothing without a resoltion. 1080p? 1440p? 4K? 8k?

Dual link DVI could handle a 10Gb connection, which was enough for 1440p 100Hz or above

These old catleap 1440p displays were dual link DVI only and were famous for overclocking to 1440p 120Hz on DVI all the way back on the Nvidia geforce 600 series
Yamakasi Catleap Monitor Club | Overclock.net

Your Displayport 1.4 'compatible' card does not support display port compression, it's locked to the lower speed per lane just like my monitor that this thread is about
Without DSC, 4k 75 is all you get at best
DP 1.4 "compatible" usually just means DP 1.2 + HDR - as I learned with my display

Then we have this gem, and i'll ask you to pay extremely close attention here.

You are the last person on the planet earth, that you will advice me of how proper scientific research this is executed.
24" screens does not require any HUGE bandwidth, DP 1.4 this is sufficient.

1. Monitor size has nothing to do with resolution, you can get 24" 4K displays with high refresh rates that your 10 series GPU cannot use to their full potential
2. What the hell does any of this have to do with me trying to understand why my monitor wasn't using DP 1.4 cable speeds
3. The next time you insult a member of this forum in a help thread, you'll find your account suspended - the stupidity of doing it to Staff member in their own help thread is just astounding.

 

[kiriakost]

2. What the hell does any of this have to do with me trying to understand why my monitor wasn't using DP 1.4 cable speeds
3. The next time you insult a member of this forum in a help thread, you'll find your account suspended - the stupidity of doing it to Staff member in their own help thread is just astounding.

This is my quick reply, for special questions, you better contact NVIDIA and Samsung, they hold the answers.
And keep it gentle, because 95% of chances this is of you to get silence as reply of your emails.

 

[Assimilator]

@Mussels there is a reason I have that particular user on ignore. They are either insane, a troll, or some combination of the two.

 

[agent_x007]

Are there any LG firmware updates for your monitor ?
Maybe it's software bug...

 

[lemonadesoda]

What does that button do? Curious, asking for a friend

 

[Mussels]

Are there any LG firmware updates for your monitor ?
Maybe it's software bug...

Cant be updated
As i mentioned in a post above, DP 1.4 'compatible' is also known as "DP 1.2 + HDR" - which means no higher bandwidth is available.

This is my quick reply, for special questions, you better contact NVIDIA and Samsung, they hold the answers.
And keep it gentle, because 95% of chances this is of you to get silence as reply of your emails.

What on earth does samsung have to do with ANYTHING in this thread?


This message is an official moderator one:
Stop wasting time with unrelated crap, or you'll get infractions any time you do.

Silence costs you nothing. This garbage posting will.

 

[Tek-Check]

Just got a new monitor that supports DP 1.2, 1.3 and 1.4 vs the old 1.2 and i'm seeing the exact same readings
Wondering if GPU-Z could be incorrect, or if I've been ripped off by a shoddy cable from amazon that claims to be 1.4, but is not

Is your monitor 4K/60 10-bit? If so, the answers are rather simple. Your monitor does not need more bandwidth than DP 1.2 can provide, even if it has DP 1.4 port. Monitors would default to lowest DP bandwidth standard it needs to convey the image even if its IC and ports support higher transmission rate.
- 4K/60 8-bit RGB image needs ~12.5 Gbps - DP 1.2 can do this
- 4K/60 10-bit RGB image needs ~16.5 Gbps - DP 1.2 can do this too

Different DisplayPort standards are not locking all features. So, for example HDR was defined in DP 1.4 standard, but it can also run on DP 1.2 link if a monitor does not need more bandwidth and if vendor implemented this feature with DP 1.2 link.

Extract from DisplayPort on WIkipedia to illustrate this point:
"HDR extensions were defined in version 1.4 of the DisplayPort standard. Some displays support these HDR extensions, but may only implement HBR2 transmission mode if the extra bandwidth of HBR3 is unnecessary (for example, on 4K 60 Hz HDR displays). Since there is no definition of what constitutes a "DisplayPort 1.4" device, some manufacturers may choose to label these as "DP 1.2" devices despite their support for DP 1.4 HDR extensions. As a result, DisplayPort "version numbers" should not be used as an indicator of HDR support. "

DP specs also include clock rates, so it's hard to tell what DP version this is running at without seeing those clock rates or HBR versions listed

In AMD Adrenaline software you can see a pixel clock and other information. Strangely, this is not displayed in GPU-Z tool.
You can easily calculate pixel clock for specific image on a monitor.

Video Timings Calculator

Is it because the link is still 5.4Gb, but with compression so GPU-Z cant report the higher speed link?

Link speed and compression are separate things. If DSC is used, data packets would still run over the same link speed and this link speed would be visible.
Some monitors with DP 1.2 IC can run DSC 1.1 up to 3:1 ratio, which was introduced before DP 1.4(a) with DSC 1.2(a). DSC 1.1 was not an integrated feature of DP 1.1 spec but monitor vendors could inslude it if monitor needed more bandwidth than ports can provide.

Using CRU the displayport and HDMI timings are very, very different on this display. That's weird.

The reason why link speed went down to DP 1.1, aka 2.7 Gbps per lane is because Nvidia's software changed RGB colour space to chroma 4:2:2. Or you changed it? Chroma 4:2:2 needs even less bandwidth on 4K/60 display, roughly 8 Gbps with roughly 520 MHz pixel clock, so display link would default to DP 1.1 with HBR protocol, as it does not need HBR2 for such image.

Tried another DP cable this one rated for 8K, same result - bandwidth doesn't go past DP 1.2 settings

I hope you understand now, from my explnations, why this was not necessary.
Also, the reason why DP and HDMI have slightly different timing is because of fine-tuning by the vendor. HDMI 2.0 link of 18 Gbps would default to 594 MHz, whereas DP has more flexibility for tuning 520-540 MHz and blanking intervals.

My HDMI 1.2 display has a single HDMI 2.0 port, and using a DP 1.4 to HDMI 2.0 adaptor, i see the higher link speeds

This is necessary as HDMI 2.0 sends 6 Gbps per each of three data lanes (18 Gbps together), so the adapter must use HBR3 with 8.1 Gbps per lane to accommodate HDMI bandwidth needs. DP 1.2 with 5.4 Gbps would not be able to fit 6 Gbps per lane from HDMI signal. Any DP-HDMI 2.0 adapter must support HBR3 protocol. If not, such adapter could support only HDMI 1.4b signal.

Why offer DP 1.4 if it doesnt get used?!?

Good question. It's because the IC chip in this monitor model is more advanced due to support for 10-bit and HDR. Such ICs come with default support for DP 1.4 in anticipation of displays with higher resolution that need more bandwidth. That's why DP 1.4 is there. I am sure LG used this IC in 4K displays with higher resolution that can use provided bandwidth. For them, using one IC on a range of different 4K monitors saves a lot of costs. You simply have a monitor with a faster port than it needs, but the main reason why you have this IC is 10-bit with HDR inside the monitor. Resolution is secondary here. They can install the same IC chip in 60Hz, 120Hz or 144Hz monitors.

The monitor and the gpu uses the DP 1.4 standard, it doesn't mean it needs to use the best transmission mode within that standard. If a lower transmission mode is good enough for the resolution and refresh rate the monitor is using, it doesn't need anything more.

This.

This seems to be the issue with my DP "1.4" display as it doesnt use HBR3 or DSC at all, but may support one of the other features like more audio channels

Yes. I explained this above. It's about IC capability for 10-bit panels. 60Hz monitors simply do not need more bandwidth. Even 4K/75Hz can use 5.4 Gbps link.

As this goes back to my original question of if GPU-Z was inaccurate or my monitor dishonest, i'm going to say that when i've tried three brands and four VESA certified "8K" cables, the monitor is the problem

I don't think there was a problem here anywhere.

DP 1.4 enables a higher compression mode - that may not be supported or used - new audio standards, and in theory uses less bandwidth for the same settings

As said, the IC chip in your monitor needs to deal with 10-bit signal and HDR. That's the most significant advancement in silicon routinely enabled with DP 1.4 standard, alongside other features your monitor simply does not need.

DP 1.4 is required to enable HDR

As said above, HDR was defined for DP 1.4, but HDR can be used by displays running on HBR2 link too, like yours.

And here we go with an active DP to HDMI cable, which is showing HBR3 as supported but not active

HBR3 must be supported in cables that convert the signal into HDMI 2.0, as explained above. 6Gbps per lane on HDMi cannot run on HBR2 link.

All in all, I cannot see anything wrong with your display. Does it run as intended now?