Can a DP1.2 monitor support HBR3?

[ecologist]

I am looking at a few 1440p monitors and it’s down to the version of DisplayPort.

The 165Hz Gigabyte M27Q rev2 has DP1.2 yet claims HBR3 is supported on the spec page. Does this mean it will support higher resolutions and framerates than normal HBR2 DP1.2? Or will it be limited to 1440p 120Hz and 4K60 @10bit?

Basically, in the 165Hz range, is it worth going for another monitor just because it has DP1.4?

I am also looking at the MSI G274QPF-QD, has anyone here got any of these monitors, I’d appreciate some feedback.

Thanks

[greatnull]

If it is really is DP 1.2 then no, no chance of supporting HDR3. DP 1.2 also does not support display stream compression, so there is really no chance of getting WQHD@10b@165hz. It would suffice for 8b.

But DP 1.2 is positively ancient, it has been finalized more that ten years ago. It would be nonsensical to design new monitor with that protocol support only. Even more insane would be designing control board with DP 1.2 AND hdmi 2.0.

If this display is recent model, then I would bet this is just typo and it actually supports DP 1.4 like pretty much anything else on the market. Ask them to clarify suspected typo in display specifications.

EDIT: According to rtings review of v2 model, it really suports just DP 1.2. Fucking cheapskate idiots then.

So no HBR3.

DisplayPort

[greatnull]

TLDR: Rtings.com is amazing source for this kind of research and comparison, ditch MSI and get LG (or something else). MSI and GB are cheapskate bastards.

Btw. your alternate choice has the same problem (rtings review here).

Seriously what the hell? That cannot be design oversight, so I suspect its the same cost cutting measure for both OEMs, and they are betting no one notices . Dropping to lower colour space is only workaround that would definitely comprose image quality.

Seriously, they have crippled their product for what, 10 USD savings per unit? Idiots.

Rtings explicitly test this for reviewers:

I personally don’t have any recommendations beyond LG ultragear series. Excellent IPS panels, but ugly as sin physical case (opinion varies, MSI and GB is the same for me). No problems regarding software and display inputs, all latest available.

Pricing is used to be considerbaly higher, but they are currently selling for pretty much the same price, so go for it.

Here is comparison of MSI vs LG 27GP850-B

and MSI vs GIGABYTE for completeness

[ecologist]

@greatnull

it really suports just DP 1.2. Fucking cheapskate idiots then.

So no HBR3.

it seems from the wiki page that DP version and HBR capability may not always match.

@greatnull

Btw. your alternate choice has the same problem

thats not the MSI G274QPF-QD, they have not reviewed it.

@greatnull

Rtings explicitly test this

they have not talked about the claimed HBR3 support on the rev 2.0

@greatnull

I personally don’t have any recommendations beyond LG ultragear series. Excellent IPS panels

yes but its £380 here. the M27Q rev2 and the MSI MSI G274QPF-QD are both £250.

thanks for the replies and including the links in the post.

[greatnull]

I wouldn’t bet on MSI et al. investing engineering time to solve this, when they are cheap enough to use control board with DP 1.2. Explicit testing also confirms that at least in GB they absolutely didnt.

It also doesn’t mean DP 1.2 can support HDB3 with certain manufacturers, it means that some could tweak transmission that HBR2 data rate would suffice when normally HBR3 would be needed.

Sorry about model, I mistook G274QPF with G274QFP. But it is from the same era, likely sharing control board. It doesn’t make me feel more confident.

they have not talked about the claimed HBR3 support on the rev 2.0

They don’t explicitly say it out loud, since in motion section I snipped, they test maximum achievable refresh rate with known source link a set target resolution+bitrate.

If they cannot get more than 120 fps over DP, you wont be able to get 180 fps over DP.

TLDR: Make sure you can return the monitor, if 180@10b fps is a dealbreaker. It would be to me.

[ecologist]

@greatnull

Sorry about model, I mistook G274QPF with G274QFP. But it is from the same era, likely sharing control board. It doesn’t make me feel more confident.

So back to the G274QPF-QD it has DP1.4, but if its like the MAG274QRF-QD on RTINGS, vs the M27Q rev2, it has:

• quantum dot + better response times at all refresh rates (edit: not correct as shown in HUB’s review)
• worse Color Accuracy (Pre-Calibration) and HDR peak brightness
• no BFI with VRR

do you think the MSI is a better pick?

@greatnull

If they cannot get more than 120 fps over DP, you wont be able to get 180 fps over DP.

@greatnull

It also doesn’t mean DP 1.2 can support HDB3 with certain manufacturers, it means that some could tweak transmission that HBR2 data rate would suffice when normally HBR3 would be needed.

thanks for clearing this up.

[anon7678104]

DisplayPort 1.4 vs. 1.2: What's the Difference?.

short answer no.

DisplayPort 1.2 offers a maximum total bandwidth of 21.6 Gbps over its four lanes and a maximum total data rate of 17.28 Gbps.
It has access to the three base DisplayPort transmission modes, including RBR, HBR, and HBR2, but it isn’t able to make use of more advanced transmissions modes, like HBR3, or any of the UHBR transmission modes

[greatnull]

I have no personal experience with BFI, but if you can tolerate it, then it is gamechanger for IPS and VA monitors.

Unless you are buying MiniLED or OLED monitor, ignore any HDR claims. They are effectively near outright lies, normal panels may pump up brightness, but contrast cannot be improved - hig dynamic range therefore cannot be achieved. This con has gone long enough.

This however is not very nice:

Response times are not very good, and effectively limit display clarity to ~~ 79 HZ worst case scenario . It can display up to 160 hz with some smearing.

How bad it could be depends on your sensitivity, hard to tell from raw data. If there is significant premium between this model vs other 120 an 144 hz monitors, then its not worth it.

Same applies to overshoot on faster overdrive modes, its subjective. I had bad experience in past with phillips VA (black-red smearing like crazy @ 60hz ), so I avoid these monitors. Graphical artifacts would drive me crazy.

Like this, even bit worse:

It can be quantified only by response time table, some transition are uniformly higher than others. Black to anything → 15 ms, grey to white 6 ms for example.

Otherwise its rather poor result compared to even LG 5year old panels i have experience with. Let me dig up results from tft-central.

But, something else to consider:

• Its 8-bit panel with FRC => 10bit signal transport will not improve quality as much as it would on 10bit native panel. Not able to receive WQHD@160@10b no longer hurts

EDIT:
Got it, I bought LG 27GL850 (review tftcentral) in 2019 for about 520€ brand new. Its also 27’ WQHD , just only 144 Hz. Worst case response time was 6.5 ms, so panel was actually capable of displaying 144 Hz content.

It got much cheaper even 1 year later, I remember seeing it sold for 280-300€ before covid.

I would recommend shopping around some more. Getting high fps gaming monitor with panel that cant actually display content fast enough is not a good deal.

Newer LG display have goten worse since then, but response times+overshoot are still better than MSI and GB, like this:

LG Cuts Price, But Not Performance - LG 32GR93U Review

[ecologist]

@greatnull

This however is not very nice

yes, HUB’s review shows the MSI as slightly worse or basically the same as the GB rev2 so not sure if the experience will be much different but only if DP1.4 is worth it

@greatnull

TLDR: Make sure you can return the monitor, if 180@10b fps is a dealbreaker. It would be to me.

can you please explain why would it be a deal breaker? I have no experience with 10-bit.

is the 120-170Hz missing 10-bit range on the GB a bad deal compared to no such issue on the MSI?

RE: LG, its out of my price range here in UK

[greatnull]

If you are paying premium for functionality that does not work, you are being fucked with. Thats the dealbreaker

Realistically, it depends. Displaying 10bit colourspace matters only if display is capable of displaying that colour range. If it does, you perceive it as colour gradients being smoother than 8bit.
MSI and GB are not however native 10 bit displays, they are 8 bit that interpolate data to match (8bit+FRC). Not good, but not bad either.

I try to vote with my wallet as much as I can, delaying purchase if necessary. But I usually obsessively research first, save up and then go overkill route.
Since my setup is both tool for work and pleasure, as long I dont do it too often its justifiable. Shelling 1k every 5-8years or so. If you spend on average 8 hours 24/7 in front of monitor, comfort gets important quickly.

Its unfortunate that many oems lie by omission pretty shamelessly, since there most popular review sites are not doing their job properly.
Reviewers like monitors unboxed and tfcentral are relatively new phenomenon, and they are still niche.

HDR rating is for example outright lie, its not technically possible to get contrast high enough on normal IPS or VA panel.
There is only one generally available panel that can do it, apple XDR PRO. Panel itself is custom, its dual layer lcd → first black and white filter, second color filter.

Other than that, they are special panels made for displaying black and white medical radiology images.

[ecologist]

@greatnull

But I usually obsessively research first,

@greatnull

Its unfortunate that many oems lie by omission pretty shamelessly, since there is most popular review sites are not doing their job properly.

Thanks bro. So you can feel the pain of trying to find accurate and basic information in this zoo, where we have to check if the claims on the box have any truth to them.

[greatnull]

TFT-central.co.uk was the first serious review site, and it still has excellent introductory material available. It also explores topics like calibration theory and howtos.

Its one man show and author had to change review style from article to youtube recently, since financials were too tight. Quality is still good.

If you are uncertain, are there any larger outlets nearby that have these monitors on display? Seeing them with your own eyes is afterall best review there is.

As long you like what you see and can live with the price, all is good.

If waiting and saving up is an option, let me show you why.

Do you see those response times (source tftcentral)? That OLED panel, and unoptimized one, since its 42’ TV. Its the cheap route to oled, if you dont mind hdmi and 42’ monster, similar models are currently at 900€.

Its route I tried and I am currently sitting in front of it. It has caveats, but smearing and artefacts are completely absent. Panel is fast enough to display even 1000 fps. Internal electronics arent, but dedicated pc monitor model can be. They were just fucking expensive ( curse you ASUS !).

Teaser:

32-inch 4K OLEDs are FINALLY Coming Soon!

[ecologist]

@greatnull

Do you see those response times

@greatnull

similar models are currently at 900€.

Braah. these numbers are a different world to IPS/VA.

@greatnull

Realistically, it depends. Displaying 10bit colourspace matters only if display is capable of displaying that colour range. If it does, you perceive it as colour gradients being smoother than 8bit.

So using a DP1.2 170Hz monitor which can only do 1440p@120Hz in 10bit mode,
if playing a game with VRR enabled while the monitor is set to 170Hz @10bit, what happens if the framerate of the game exceeds 120Hz, does the color depth drop to 8-bit until famerate is at least 120Hz?

[ecologist]

@anon7678104

DisplayPort 1.4 vs. 1.2: What’s the Difference?.

short answer no.

yes, which means Gigabyte are lying about HBR3 support on DP1.2

[greatnull]

@ecologist

if playing a game with VRR enabled while the monitor is set to 170Hz @10bit, what happens if the framerate of the game exceeds 120Hz, does the color depth drop to 8-bit until famerate is at least 120Hz?

If monitor does not support HBR3 and does not do out of spec mitigation, then you will not be able to select 170@10b at all, just 120@10b, regardless to VRR.

Color depth also does not change dynamically, i am pretty sure it cant even be done without visible display disruption (black screen as display changes mode).

[ecologist]

@greatnull

If monitor does not support HBR3 and does not do out of spec mitigation, then you will not be able to select 170@10b at all, just 120@10b, regardless to VRR.

@greatnull

Color depth also does not change dynamically,

thanks for explaining. I guess the MSI with DP1.4 can be set to 170@10b?

[greatnull]

Yep, if it actually has dp 1.4 then you should not encounter any issues.

[anon7678104]

could just be a misprint.
or they mean up to 165hz as 170hz is marked as an oc profile.

if you can drop the refresh to 165hz and see for yourself.

[ecologist]

@greatnull

If monitor does not support HBR3 and does not do out of spec mitigation, then you will not be able to select 170@10b at all, just 120@10b, regardless to VRR.

Color depth also does not change dynamically,

@anon7678104

could just be a misprint.
or they mean up to 165hz as 170hz is marked as an oc profile.

if you can drop the refresh to 165hz and see for yourself.

So I got the GB M27Q, and I can confirm what greatnull said.
Using DP, the max refresh rate at 10-bit is 120Hz, setting it any high lowers color depth in the Nvidia control panel automatically to 8-bit and can not be set to 10-bit.

10bit-144Hz can be set in the NV panel but only when selecting YCbCr422 or YCbCr444 instead of RGB as color format.

While looking into this, I found that 10-bit can be done on the gpu instead of the display using dithering, does anyone have any experience with this?

[greatnull]

While looking into this, I found that 10-bit can be done on the gpu instead of the display using dithering, does anyone have any experience with this?
Your observation is in line of what we dicussed before. GB M27Q is “technically 10bit capable” via specific FRX approximation. It does not have native 10bit panel. What does it mean?

Your display pipeline can output 10b at given res@freq AND your display accepts it (it advertises itself as capable of receiving 10bit signal).

Since you have 8bit+FRC display, it can receive 10 bit signal, then the display transforms it into dynamic 8 bit pattern via FRC magic, that approximates native 10bit output.

So not as good as native 10bit, not as bad as plain 8 bit with all else being equal. Most people are not capable of telling the difference and absolute majority of consumable content is mastered to 8 bit.

Sidenote: Poorly mastered 8bit content on good 10bit monitor can look worse that on normal one. Look up posterization artifacts if you want to know more

You can test it out for yourself. Get yourself something mastered to 10bit colour depth ( cough torrent 1080p hevc 10bit section cough) and play it in 8bit colour space, then in 10 bit colour space.

If you don’t see meaningful difference on your monitor, then don’t sweat it.
It becomes interesting if you are into photography or video editing. And good monitors that are good for that are 60hz only and many timers more expensive.