ELMB-SYNC on TUF Gaming VG27BQ

Ask about motion blur reduction in gaming monitors. Includes ULMB (Ultra Low Motion Blur), NVIDIA LightBoost, ASUS ELMB, BenQ/Zowie DyAc, Turbo240, ToastyX Strobelight, etc.
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RealNC
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Re: ELMB-SYNC on TUF Gaming VG27BQ

Post by RealNC » 27 Sep 2019, 08:33

knypol wrote:Hmm so if my monitor (pg258q) can strobe in 100, 120 and 144Hz the least amount of crosstalk i should see is on 100Hz? When i do ufo test i can clearly see a lot less crosstalk on 144 than 120 or 100...or i misunderstood smth?
It depends on the monitor. Different models use different timings. Usually, you get the best results when you run lower Hz but at high-Hz timings. This is sometimes called "accelerated scanout."

What you do is use a custom 100Hz mode where you raise the VT (vertical total) of the mode until the pixel clock reaches the same value as the pixel clock you have at 144Hz (or even higher, if your monitor can still strobe.) The result of this is that you get a frame every 10ms (100Hz), but each frame takes 6.9ms to scan out (144Hz scanout speed,) not 10ms. This usually means the pixels at the bottom of the screen transition earlier to the new frame, and this reduces crosstalk because each strobe is still spaced 10ms apart, giving pixels more time to transition before they become visible.

This isn't 100% guaranteed though. Again, depends on the monitor. You can try though. Also note that some monitors will not allow this at all. Most do, however.

And a final note: Some monitors already do this accelerated scanout themselves when you choose a lower Hz. In these cases, you obviously are already getting the benefits of this trick and you don't need to customize the lower Hz modes. You can tell if this is the case or not in your monitor by comparing the pixel clocks of the lower Hz modes to the pixel clock of the highest Hz mode that supports strobing.
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Re: ELMB-SYNC on TUF Gaming VG27BQ

Post by knypol » 27 Sep 2019, 12:51

RealNC wrote:...

And a final note: Some monitors already do this accelerated scanout themselves when you choose a lower Hz. In these cases, you obviously are already getting the benefits of this trick and you don't need to customize the lower Hz modes. You can tell if this is the case or not in your monitor by comparing the pixel clocks of the lower Hz modes to the pixel clock of the highest Hz mode that supports strobing.

I think i read somewhere in this forum that gsync (ulmb) monitors are done in this way...

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Re: ELMB-SYNC on TUF Gaming VG27BQ

Post by RealNC » 27 Sep 2019, 17:41

knypol wrote:I think i read somewhere in this forum that gsync (ulmb) monitors are done in this way...
Not sure. Mine doesn't.
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Re: ELMB-SYNC on TUF Gaming VG27BQ

Post by Chief Blur Buster » 27 Sep 2019, 21:47

RealNC wrote:
knypol wrote:I think i read somewhere in this forum that gsync (ulmb) monitors are done in this way...
Not sure. Mine doesn't.
knypol, I think there's a potential confusion what "accelerated scanout" refers to.

(1) GSYNC/FreeSync natural always-max velocity scanout at any Hz (lowers lag), even RealNC's ViewSonic XG2703-GS does this too -- (GOOD)

(2) Scanrate conversion built into monitors for fixed-scanrate panels (e.g. 240Hz panels that ends up adding a bit of lag for 60Hz consoles, only having lowest lag for 240Hz signals) where it buffers 60Hz slow-scanning signal for accelerated 1/240sec scanout -- (BAD)

(3) Large Vertical Totals used by Quick Frame Transport (fast refresh cycle delivery over cable) -- (GOOD)

(4) Large Vertical Totals used for strobe crosstalk reduction (GOOD)

(Note: #3 and #4 can be done at the same time, and sometimes #3/#4 can cancel-out #2 for well-designed monitor firmwares, though no consoles support #3 nor #4, and only XBox support #1)

Be very careful about terminology around here, "accelerated scanout" may be good and may be bad, depending on context.
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Re: ELMB-SYNC on TUF Gaming VG27BQ

Post by Razorless » 28 Sep 2019, 08:45

I now have the VG27BQ (TN Version) and it shows significant crosstalk in the upper half of the screen, similar to my old XL2411Z without VT tweaks. Compared to VT-tweaked custom resolutions and the ancient lightboost of my VG248QE, it is quite disturbing.

Sadly, the crosstalk is pretty much the same between 80-165 Hz, so limiting the FPS with RTSS does not help. Also, I created a 120 Hz custom resolution with a similar pixel clock as 165 Hz, with little to no effect visible in the UFO-invasion test. Ghosting is also quite pronounced all across the screen.

As an early verdict, I would say that anything above 90 FPS looks better on lightboost 120 Hz (or rougly 75 FPS @ 100 Hz). Lower FPS look better with ELMB-Sync, despite the increased crosstalk and ghosting.
In terms of brightness, ELMB-Sync is a lot brighter than lightboost@VG248QE or VT-tweaks@XL2411Z. The backlight does show more bleeding in the middle at the top and bottom, but it is only really visible in scenes with constant, even movement (like the UFO test). During gameplay (Witcher 3), I did not notice it.
Colors and contrast are a lot better than lightboost and Benq-MBR. The included sRGB profile showed good results out-of-the-box and after calibration with my Spyder4Pro it showed 99% sRGB coverage.
Adaptive sync I have only tested with NVIDIA (GTX 1070) so far. It works well and looks better than expected. I was never bothered much by tearing, but after playing a bit with adaptive sync, it cannot be unseen and it is hard to go back.

So, is it worth it? To be honest, at the beginning I was pretty disappointed. I was expecting the holy grail and instead got a cup of good tea. It is nice, but not was I was hoping for. However, I still think it was worth the upgrade. Here is a summary of the pros and cons compared to the VG248QE and XL2411Z:

+ bigger screen, higher resolution, smaller bezels
+ better colors and contrast
+ a lot brighter
+ adaptive sync, no more tearing and stuttering (works with NVIDIA and AMD)
+ adaptive strobing (looks better if FPS is around 25% below a certain frequency, eg. below 90 FPS @ 120 Hz fixed strobing looks worse than adaptive strobing despite more crosstalk)

- significantly more crosstalk, looks a lot worse when FPS=Hz
- ghosting across the entire screen, can be annoying with a dark background
- a little more backlight bleeding

edit: ghosting is also quite pronounced

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Re: ELMB-SYNC on TUF Gaming VG27BQ

Post by Chief Blur Buster » 01 Oct 2019, 18:57

One big problem is that scaler makers have been building-in hardware limitations to their panels that prevent strobe from overapping VBI. The scaler manufacturers are mainly based in China (or Taiwan).

To eliminate the crosstalk at top edge, you need to turn ON the backlight near the end of the previous refresh cycle, and turn OFF the backlight during VBI.

Unfortunately, many scalers PWM electronics only can do the ON-OFF rise-fall after the VSYNC, which is terrible for crosstalk at the top edge. I've repeatedly tried to communicate these to multiple Chinese-speaking engineers and it's not always easy to communicate the necessary pre-requisites of custom strobe phases. The scaler/tcon makers keep saying things like "Hardware Limitation".

Scaler vendors working for multiple monitor manufacturers make this mistake, and only a few (e.g. NVIDIA) has properly figured it out.

It's even harder for VRR strobing because it can't always predict when the next VSYNC is, but they could at least design it so that strobing happens at the end of a scanout. It would be a massive improvment to strobe quality in reduced crosstalk, especially at lower frame rates, and the crosstalk would only appear when framerates went really high, since low frame rates at high Hz VRR is effective large vertical totals in realtime (since VRR = varying vertical totals!). By milking that properly, a manufacturer can dynamically reduce crosstalk at lower frame rates, rather than have max-Hz crosstalk (e.g. 80fps with the crosstalk of 144Hz strobing).
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Re: ELMB-SYNC on TUF Gaming VG27BQ

Post by Vega » 03 Oct 2019, 14:26

Ya I decided to pass on the TUF ELMB sync monitors. Apparently strobe+VRR was too much of a hurdle to do properly. Too much cross-talk, even on the TN model defeats the purpose.

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Re: ELMB-SYNC on TUF Gaming VG27BQ

Post by Stig Vildmark » 06 Oct 2019, 03:34

Does anyone know if ELMB-SYNC works on both video cards manufacturer?

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Re: ELMB-SYNC on TUF Gaming VG27BQ

Post by Chief Blur Buster » 06 Oct 2019, 19:13

Stig Vildmark wrote:Does anyone know if ELMB-SYNC works on both video cards manufacturer?
Yes, under the "G-SYNC Compatible = FreeSync" route. It is not NVIDIA certified though, but you an force FreeSync on any DisplayPort compatible FreeSync monitors (And I believe, eventually, probably also HDMI given the new NVIDIA compatibility with the VRR OLED).

At the technological development level, strobing inherently isn't locked to a particular GPU. It's by vendor choice (such as NVIDIA) to DRM-lock a specific strobe technology such as LightBoost or ULMB (which happen to be above-average-quality strobe technologies), to cover the extra engineering & R&D costs of the technology by the follow-on GPU sales.
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       To support Blur Busters:
       • Official List of Best Gaming Monitors
       • List of G-SYNC Monitors
       • List of FreeSync Monitors
       • List of Ultrawide Monitors

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Re: ELMB-SYNC on TUF Gaming

Post by Stig Vildmark » 09 Oct 2019, 05:52

Chief Blur Buster wrote:
Stig Vildmark wrote:Does anyone know if ELMB-SYNC works on both video cards manufacturer?
Yes, ....
Thank you, one thing lead to another and i acted right away since my monitor is dead. I bought a new monitor and a Gainward RTX 2070 that turned out to have some issues. I don't know if it was a driver issue or a manufactory error. But the lagspikes and high dpc latency in desktop made it unusable. I returned it to buy a AMD card, i switched camp incase it was a generic nvidia driver issue with my x99s gaming 7 motherboard.


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I was going to buy the VG27BQ.... but i ended up with the VG32VQ. It is a very personal choice but i couldn't stand viewing something dark on IPS. My expression so far with the VG32VQ is positive, it's is a step down in movies compared to my crt. But the larger size 31.5" vs 22.5" gives it another level of immersion, all due to its size. So far it feel like an upgrade in gaming, at least in bright games since i have yet to play any real dark ones. The monitor i got didn't have any pixel errors, it did have a few light imperfections that i only noticed when the screen was completly black. It's not perfect black, but i can live with this. A quick calibration with idisplay pro give me 97% of SRGB without elmb. I will redo it when i have time.

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(The Monitor is off in this image, you will not get these blacks. I took this picture of the GPU before i installed it)


I have forgotten the name of my old account. But i ran two 980 ti in sli. I asked since i wanted to know about the Nvidia support for elmb. I was forced to upgrade since my 980 ti only had support for G-sync. This monitor was suppose to be a replacement to my old crt monitor that broke. Here is a old picture of that setup.
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The flat screen with poor viewing angles to the left is a BenQ 27" XL2720Z. The TN panel was not enough to replace my CRT, so i ended up using it in portrait mode before i gave it away to a friend. It's blur reduction do look better than the VG32VQ with elmb, both are awful compared to CRT. BenQ 27" XL2720Z have less of that double /triple image effect than VG32VQ. But the blacks on XL2720Z are just painful, while VG32VQ is bearable in movies.

VG32VQ was able to compensate for it's lack of color with size, the XL2720Z could not since it had almost the same height as my CRT monitor. XL2720Z had to many downsides compared to my FW900, the ony plus side was it's wider view. So far, the VG32VQ is a good replacement to my crt, the postives are enough for me to compromise. I can give a more detailed review after i have gotten used to it. I highly recommend that every user take a good look on the blacks before they buy a VA or IPS monitor. Once i tried 32" , the 22.5" CRT just feels too small for FPS gaming. I will probably stay with VG32VQ until there is a oled alternative.

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