Some Freesync Questions

Talk about AMD's FreeSync and VESA AdaptiveSync, which are variable refresh rate technologies. They also eliminate stutters, and eliminate tearing. List of FreeSync Monitors.
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Chief Blur Buster
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Re: Some Freesync Questions

Post by Chief Blur Buster » 01 Jul 2020, 18:07

lc155 wrote:
01 Jul 2020, 15:59
So in practical terms, to see if I understand this correctly, given my first example:

With a 144Hz G-SYNC Compatible 38GN950, I can safely leave the monitor at 144Hz (or 160Hz with the supported OC) and, while running Dolphin, LFC will ensure G-SYNC is always activated even if the game is running at 30fps instead of 50/60. G-SYNC will also ensure that the frames are updating at the maximum possible speed instead of waiting for fixed Hz intervals, meaning that lag will be as minimal as it can possibly be, and you won't suffer from juddering in motion caused by non-integer division (such as a 24fps film running on a 60Hz monitor where it doesn't cleanly divide). As G-SYNC is taing care of all of this, changing the monitor refresh rate to be an integer division of the game (such as 120Hz for a 60Hz game) is therefore redundant and unnecessary.

Does that sound right?
Correct.

The software controls the refresh cycles of a VRR monitor. Frame presentation immediately begins the refresh cycle.

For software developers, your Update() or Present() or glxxSwapBuffers() is controlling the timing of refresh cycles 😊

The frame rate is the refresh rate, the refresh rate is the frame rate, there is no difference. 55fps looks like perfect 55Hz VSYNC ON. 75fps looks like perfect 75Hz VSYNC ON. And framerate fluctuations can go stutterless, as seen in animation at www.testufo.com/vrr
lc155 wrote:
01 Jul 2020, 15:59
also read (I think from you) somewhere that while the implementation of LFC (and the G-SYNC module version of it I think) can have issues with stuttering at low frames, this has more to do with uneven frame pacing/timing (aka framerate is jumping all over the place and isn't stable). In short, a 30fps emulated game that is running stable should be a perfect application for smooth LFC?
Correct.

LFC stutter is caused by unpredictable frame presentation colliding with a monitor that’s still busy scanning out.

The new frame needs to wait for the monitor to finish scanning out a repeat-refresh (to prevent the refresh from fading....kind of like display equivalent of a a DRAM refresh). That frame wait cycle creates a disjoint between presentation time and visibility time, creating stutter.

But if frame rate is consistent, the repeat-refresh(es) will be predictively timed successfully between frames (without timing interference)

Also a very high max Hz, such as 240Hs, means the LFC penalty is only, at worst, a 4.2ms delay. And the LFC prediction logic has wider safety margin of timing windows since the monitor is idling much longer between ultra-fast-velocity scanouts. Also, even if LFC collides with a monitor-busy, the worst case stutter-jump only 1/4 the stutter width as 60Hz. So wide VRR ranges (30Hz-240Hz) usually have no visible LFC stutter even for erratic frame rates below Hz (erratic framerate games).

Also, are you considering motion blur reduction too? See https://blurbusters.com/blur-busters-approved
lc155 wrote:
01 Jul 2020, 15:59
I believe this was the video in question. He talks about how certain arcade games run at really esoteric framerates which result in juddering on standard displays, whereas VRR can kick in here and correct for that (as forcing old games to run at higher frame rates just results in them speeding up). It's a fairly old video now but I imagine the point remains the same.
Yes,

VRR allows the emulator frame rate to be the refresh rate. There is no semantic difference between frame rate and refresh rate when inside VRR range. Problem solved.
Head of Blur Busters - BlurBusters.com | TestUFO.com | Follow @BlurBusters on Twitter

       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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jorimt
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Re: Some Freesync Questions

Post by jorimt » 01 Jul 2020, 18:47

Chief Blur Buster wrote:
01 Jul 2020, 17:51
If you use RTSS or a well framepaced 8bit emulator, one only needs about 60.5Hz for VRR to engage at 60fps.

Emulators and RTSS have consistent framepacing. RTSS is precise enough and the refresh rate slow enough (half Hz = 8ms) that a 0.5fps cap-below helps emulators a LOT. Also GPU use closer to 50% instead of 100% while in Performance Mode, often helps more accurate cap-based framepacing. Most emulators don’t drive a GPU into the ground, so tighter capping is more practical. The frametime jitter will be small enough that 0.5Hz-below is enough breathing room for the emulator use-case.

3fps-below is just well-tested boilerplate VRR advice that is good, but the reality is sometimes 0.2fps-to-0.5fps below is OK for emulator use. Also, 5-to-8fps-below is probably sometimes needed for 280Hz-360Hz, due to ultrashort refreshtimes.
This is true; a certain era of emulated side-scrollers achieve steady enough frametime performance to allow what modern triple AAA games would not.

That said, I was limiting my explanation to out-of-box behavior of a 60Hz VRR monitor, but a slight overclock for this purpose is indeed a viable option worth mentioning in the context of emulation.
(jorimt: /jor-uhm-tee/)
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Re: Some Freesync Questions

Post by lc155 » 01 Jul 2020, 22:35

jorimt wrote:
01 Jul 2020, 17:34
lc155 wrote:
01 Jul 2020, 17:16
I was vaguely aware, but have no personal experience with it as I'm just used to just having all my emulators separated, perhaps I'll give it a try. I just remembered hearing about RetroArch specific issues and figured it was perhaps more involved than a simple aggregate interface. Do they develop some bundled emulators further or something? I'll admit I have been out of the scene for a number of years and was interested in coming back to it recently.
Retroarch is a "front end" for emulators. You load the emulators as "cores," and they then, for the most part, behave as they do when standalone. You just manage them differently:
https://www.retroarch.com/
Noted. I'll definitely check it out when I start using emulators again, whenever that is (hopefully soon).
jorimt wrote:
01 Jul 2020, 17:34
lc155 wrote:
30 Jun 2020, 21:39
Just to clarify, what do you mean specifically by 'if your VRR monitor is above 60Hz'. Is there something special about that, or did you mean 'If the monitor is at or above 60Hz'? Since in the linked video, juddering was an issue with 60Hz when the game ran at 59.1 or 54 or whatever that didn't integer divide. Just making sure I understand properly. I never knew how complex monitor refresh tech really was until I started looking into this stuff.
VRR needs a few frames of breathing room below the max refresh rate (-3 FPS is typically safe) to stay within range, else it reverts to fixed refresh rate behavior. This is mainly due to the fact that 100% perfect frametime is not achievable with FPS limiters (or modern systems).

So if you have a 60.1 FPS emulated title, for instance, and only have a 60Hz G-SYNC monitor, VRR will disengage. However, if you have, say, a 144Hz monitor, you'll have plenty of overhead for the game to run at 60.1hz and remain in the VRR range.

Emulated games that run at 54 FPS however, would be well enough within the refresh rate to use a 60Hz VRR monitor, for instance.
Ah, that makes a lot more sense now. I had wondered why the standard recommendation was to cap frames 3fps below the refresh rate in standard games as well. Thanks.

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Re: Some Freesync Questions

Post by lc155 » 01 Jul 2020, 22:36

Chief Blur Buster wrote:
01 Jul 2020, 17:51
If you use RTSS or a well framepaced 8bit emulator, one only needs about 60.5Hz for VRR to engage at 60fps.

Emulators and RTSS have consistent framepacing. RTSS is precise enough and the refresh rate slow enough (half Hz = 8ms) that a 0.5fps cap-below helps emulators a LOT. Also GPU use closer to 50% instead of 100% while in Performance Mode, often helps more accurate cap-based framepacing. Most emulators don’t drive a GPU into the ground, so tighter capping is more practical. The frametime jitter will be small enough that 0.5Hz-below is enough breathing room for the emulator use-case.

3fps-below is just well-tested boilerplate VRR advice that is good, but the reality is sometimes 0.2fps-to-0.5fps below is OK for emulator use. Also, 5-to-8fps-below is probably sometimes needed for 280Hz-360Hz, due to ultrashort refreshtimes.

The good news:
Overclock your 4K 60Hz “40-60Hz” generic FreeSync monitor to 60.5Hz, to enable low-lag VRR-operated 60Hz, while enjoying MAME HLSL CRT effects enhanced by the 4K resolution. Even 60fps at 60.25Hz VRR actually helps emulator latency, depending on emulator, GPU load, Performance Mode (zero power management jitter), etc.
Thanks for the very insightful response. At least in my situation it won't be something I will have to encounter as I'll probably stick with UW and move on from my planned monitor when 5k2k 144Hz is a thing. Could be many years from now. Still, that info is probably useful to anyone coming across this thread with similar questions.

lc155
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Re: Some Freesync Questions

Post by lc155 » 01 Jul 2020, 22:38

Chief Blur Buster wrote:
01 Jul 2020, 18:07
lc155 wrote:
01 Jul 2020, 15:59
So in practical terms, to see if I understand this correctly, given my first example:

With a 144Hz G-SYNC Compatible 38GN950, I can safely leave the monitor at 144Hz (or 160Hz with the supported OC) and, while running Dolphin, LFC will ensure G-SYNC is always activated even if the game is running at 30fps instead of 50/60. G-SYNC will also ensure that the frames are updating at the maximum possible speed instead of waiting for fixed Hz intervals, meaning that lag will be as minimal as it can possibly be, and you won't suffer from juddering in motion caused by non-integer division (such as a 24fps film running on a 60Hz monitor where it doesn't cleanly divide). As G-SYNC is taing care of all of this, changing the monitor refresh rate to be an integer division of the game (such as 120Hz for a 60Hz game) is therefore redundant and unnecessary.

Does that sound right?
Correct.

The software controls the refresh cycles of a VRR monitor. Frame presentation immediately begins the refresh cycle.

For software developers, your Update() or Present() or glxxSwapBuffers() is controlling the timing of refresh cycles 😊

The frame rate is the refresh rate, the refresh rate is the frame rate, there is no difference. 55fps looks like perfect 55Hz VSYNC ON. 75fps looks like perfect 75Hz VSYNC ON. And framerate fluctuations can go stutterless, as seen in animation at www.testufo.com/vrr
Perfect. Glad I'm getting the hang of this. And yeah, I realised I was swapping between fps and Hz randomly.

Chief Blur Buster wrote:
01 Jul 2020, 18:07
lc155 wrote:
01 Jul 2020, 15:59
also read (I think from you) somewhere that while the implementation of LFC (and the G-SYNC module version of it I think) can have issues with stuttering at low frames, this has more to do with uneven frame pacing/timing (aka framerate is jumping all over the place and isn't stable). In short, a 30fps emulated game that is running stable should be a perfect application for smooth LFC?
Correct.

LFC stutter is caused by unpredictable frame presentation colliding with a monitor that’s still busy scanning out.

The new frame needs to wait for the monitor to finish scanning out a repeat-refresh (to prevent the refresh from fading....kind of like display equivalent of a a DRAM refresh). That frame wait cycle creates a disjoint between presentation time and visibility time, creating stutter.

But if frame rate is consistent, the repeat-refresh(es) will be predictively timed successfully between frames (without timing interference)

Also a very high max Hz, such as 240Hs, means the LFC penalty is only, at worst, a 4.2ms delay. And the LFC prediction logic has wider safety margin of timing windows since the monitor is idling much longer between ultra-fast-velocity scanouts. Also, even if LFC collides with a monitor-busy, the worst case stutter-jump only 1/4 the stutter width as 60Hz. So wide VRR ranges (30Hz-240Hz) usually have no visible LFC stutter even for erratic frame rates below Hz (erratic framerate games).

Also, are you considering motion blur reduction too? See https://blurbusters.com/blur-busters-approved

Good to know the reasoning why, thanks.

I haven't actually considered motion blur reduction, nor thought about it. Is this something the 38GN950 is capable of? Are there downsides to it?

Chief Blur Buster wrote:
01 Jul 2020, 18:07
lc155 wrote:
01 Jul 2020, 15:59
I believe this was the video in question. He talks about how certain arcade games run at really esoteric framerates which result in juddering on standard displays, whereas VRR can kick in here and correct for that (as forcing old games to run at higher frame rates just results in them speeding up). It's a fairly old video now but I imagine the point remains the same.
Yes,

VRR allows the emulator frame rate to be the refresh rate. There is no semantic difference between frame rate and refresh rate when inside VRR range. Problem solved.
Simple and to the point. Perfect. 😊

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Re: Some Freesync Questions

Post by Chief Blur Buster » 01 Jul 2020, 22:41

lc155 wrote:
01 Jul 2020, 22:36
Thanks for the very insightful response. At least in my situation it won't be something I will have to encounter as I'll probably stick with UW and move on from my planned monitor when 5k2k 144Hz is a thing. Could be many years from now. Still, that info is probably useful to anyone coming across this thread with similar questions.
It’s coming this year. Samsung has a luxury 240Hz ultrawide coming with roughly that resolution, it is called the Samsung Odyssey C9.

Also, you should know that 240Hz has 1/4 the scrolling motionblur, so you can still enjoy web browsing better than a 120 Hz iPad. 😊 .... You can strive beyond 144Hz if you like clearer scrolling / panning / etc. 240 Hz is no longer just for esports.
Head of Blur Busters - BlurBusters.com | TestUFO.com | Follow @BlurBusters on Twitter

       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: Some Freesync Questions

Post by lc155 » 02 Jul 2020, 11:15

Chief Blur Buster wrote:
01 Jul 2020, 22:41
lc155 wrote:
01 Jul 2020, 22:36
Thanks for the very insightful response. At least in my situation it won't be something I will have to encounter as I'll probably stick with UW and move on from my planned monitor when 5k2k 144Hz is a thing. Could be many years from now. Still, that info is probably useful to anyone coming across this thread with similar questions.
It’s coming this year. Samsung has a luxury 240Hz ultrawide coming with roughly that resolution, it is called the Samsung Odyssey C9.

Also, you should know that 240Hz has 1/4 the scrolling motionblur, so you can still enjoy web browsing better than a 120 Hz iPad. 😊 .... You can strive beyond 144Hz if you like clearer scrolling / panning / etc. 240 Hz is no longer just for esports.
Samsung's monitors tend to be a bit too much for me. Not a fan of the fish-eye going on in games with 32:9 and I don't like how aggressive they are with their curves.

I'm ignorant on how good fast motion stuff is as I'm used to 60Hz, so I'm sure 144Hz will be a gigantic leap for me as it is!

I did some more reading on the motion blur reduction stuff you mentioned and it seems the 38GN950 comes with this as a feature mode - is that why you mentioned it?

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Re: Some Freesync Questions

Post by Chief Blur Buster » 02 Jul 2020, 12:01

lc155 wrote:
02 Jul 2020, 11:15
I'm ignorant on how good fast motion stuff is as I'm used to 60Hz, so I'm sure 144Hz will be a gigantic leap for me as it is!
Yes, 144Hz will be about 2.4x clearer motion. For your next gaming monitor, you should at least include VRR and 120Hz+.

1. Go look at www.testufo.com

2. Different refresh rates will look like this:
Image

You will immediately recognize the 60Hz matches what you saw at www.testufo.com
Now, upgrading your refresh rate, you'll see that moving objects will have WAY less motion blur.

The well-noticed property of flicker-free displays is that you need to double refresh rate in order to halve motion blur. Around here, we tend to recommend geometric refresh rate upgrades. Example: 60Hz -> 144Hz -> 360Hz (approximate 2.5x jumps).
lc155 wrote:
02 Jul 2020, 11:15
I did some more reading on the motion blur reduction stuff you mentioned and it seems the 38GN950 comes with this as a feature mode - is that why you mentioned it?
Yes. That said, it's optional. Just having 144Hz, however, will reduce your motion blur (of full 144fps framerates) by about 60/144ths the original display motion blur. GtG is fast enough to not be a noticeable error margin to this motion clarity improvement.

Display motion blur is often caused by eye-tracking motion, as demonstrated in animation at www.testufo.com/eyetracking and www.testufo.com/persistence -- see those amazing optical illusions generated by eye-tracking-based display motion blur. For more information about the science of why this happens, I explain at Blur Busters Law: The Amazing Journey To Future 1000 Hz Displays.

There are two ways to reduce display motion blur:
1. Shorten frame visibility time by flashing them (black period between refreshes)
2. Shorten frame visibility time by adding more frames (briefer-visibility frames)

The advantage of (#1) is you don't need more refresh rate to reduce motion blur. You can reduce display motion blur of 120Hz by 90% without increasing the refresh rate. However, the latter (#2) is more natural looking, and better on the eyes, but definitely requires a more powerful GPU.

Be noted that motion blur reduction modes can sometimes have issues. Blur Busters now usually prefers to reduce motion blur by higher Hz (which is why we're big fans of future 1000Hz monitors) instead of via flashing/flicker/strobing/phosphor. It's an amazing technique, allowing LCDs to become CRT motion clarity, but can have some side effects.

Also, Strobed Nano IPS panels using the KSF phosphor, also has a red-colored afterimage crosstalk, strobed problems from KSF phosphor in Nano IPS panels, but I'm not sure if they fixed it for the 38GN950. Nontheless, you can probably ignore the strobed feature for now, since you're used to 60 Hz, and simply using the refresh rate instead

However, I really like the look of Nano IPS colors in non-strobed mode, the colors are deliciously bright and red, and you will be very, very pleased with the LG 38GN950 monitor.

3840x1600 modern "1ms GtG" IPS with wide color gamut, 144 Hz overclockable to 160 Hz -- should probably look great with any work, PhotoShop, Visual Studio, etc. Short of going to a locally-dimmed LCD, it's probably among the best ultrawide combo as long as you aren't having high expectations for the strobe backlight mode.

I currently have multiple different monitors here, and I have some Nano IPS. For anything non-strobed operation, the colors of a Nano IPS is one of the better I've seen in a desktop LCD short of a multithousand-count full array local dimmed panel (those still cost $1500-$2000+ in a desktop monitor).

For you, the LG 38GN950 will be essentially plug-n-play for the majority of your apps. You might just need to do some minor per-app configuring as described (e.g. emulators etc).
Head of Blur Busters - BlurBusters.com | TestUFO.com | Follow @BlurBusters on Twitter

       To support Blur Busters:
       • Official List of Best Gaming Monitors
       • List of G-SYNC Monitors
       • List of FreeSync Monitors
       • List of Ultrawide Monitors

lc155
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Re: Some Freesync Questions

Post by lc155 » 02 Jul 2020, 17:27

Chief Blur Buster wrote:
02 Jul 2020, 12:01

Yes, 144Hz will be about 2.4x clearer motion. For your next gaming monitor, you should at least include VRR and 120Hz+.

1. Go look at www.testufo.com

2. Different refresh rates will look like this:
Image

You will immediately recognize the 60Hz matches what you saw at www.testufo.com
Now, upgrading your refresh rate, you'll see that moving objects will have WAY less motion blur.

The well-noticed property of flicker-free displays is that you need to double refresh rate in order to halve motion blur. Around here, we tend to recommend geometric refresh rate upgrades. Example: 60Hz -> 144Hz -> 360Hz (approximate 2.5x jumps).
I'm pretty excited to see the difference, as I'm so used to 60Hz that it still feels natural to me. They say ignorance is bliss!

I had noticed the first 360Hz displays had started to become available. Wonder how long it will take for that one to trickle down, considering 240Hz is becoming more commonplace in the budget sector.
Chief Blur Buster wrote:
02 Jul 2020, 12:01
Yes. That said, it's optional. Just having 144Hz, however, will reduce your motion blur (of full 144fps framerates) by about 60/144ths the original display motion blur. GtG is fast enough to not be a noticeable error margin to this motion clarity improvement.

Display motion blur is often caused by eye-tracking motion, as demonstrated in animation at www.testufo.com/eyetracking and www.testufo.com/persistence -- see those amazing optical illusions generated by eye-tracking-based display motion blur. For more information about the science of why this happens, I explain at Blur Busters Law: The Amazing Journey To Future 1000 Hz Displays.

There are two ways to reduce display motion blur:
1. Shorten frame visibility time by flashing them (black period between refreshes)
2. Shorten frame visibility time by adding more frames (briefer-visibility frames)

The advantage of (#1) is you don't need more refresh rate to reduce motion blur. You can reduce display motion blur of 120Hz by 90% without increasing the refresh rate. However, the latter (#2) is more natural looking, and better on the eyes, but definitely requires a more powerful GPU.

Be noted that motion blur reduction modes can sometimes have issues. Blur Busters now usually prefers to reduce motion blur by higher Hz (which is why we're big fans of future 1000Hz monitors) instead of via flashing/flicker/strobing/phosphor. It's an amazing technique, allowing LCDs to become CRT motion clarity, but can have some side effects.
That motion blur test is pretty neat, especially how different it looks depending on whether my eyes are focusing on the dots or the UFO in the middle. I will be sure to come back to these tests when I have the monitor, so I can compare it to my older 60Hz one for sure.

In my reading of the motion blur reduction modes on monitors, I did read that it wasn't a perfect implementation and can definitely have certain issues.
Chief Blur Buster wrote:
02 Jul 2020, 12:01
Also, Strobed Nano IPS panels using the KSF phosphor, also has a red-colored afterimage crosstalk, strobed problems from KSF phosphor in Nano IPS panels, but I'm not sure if they fixed it for the 38GN950. Nontheless, you can probably ignore the strobed feature for now, since you're used to 60 Hz, and simply using the refresh rate instead

However, I really like the look of Nano IPS colors in non-strobed mode, the colors are deliciously bright and red, and you will be very, very pleased with the LG 38GN950 monitor.

3840x1600 modern "1ms GtG" IPS with wide color gamut, 144 Hz overclockable to 160 Hz -- should probably look great with any work, PhotoShop, Visual Studio, etc. Short of going to a locally-dimmed LCD, it's probably among the best ultrawide combo as long as you aren't having high expectations for the strobe backlight mode.

I currently have multiple different monitors here, and I have some Nano IPS. For anything non-strobed operation, the colors of a Nano IPS is one of the better I've seen in a desktop LCD short of a multithousand-count full array local dimmed panel (those still cost $1500-$2000+ in a desktop monitor).
Noted. I can't see myself wanting even more at this point in time, you're right. Quite happy to stick with the refresh rate method for the fewest issues (from what I can read, if you can't maintain a consistent 120/144 with ULMB it doesn't work well, so this seems highly game dependent. It also won't work for emulators as you'll just get duplicated images, it would seem, as strobing works best at higher refresh rates with matching frame rates?)

I should probably note that I'm not the biggest fan of wide gamut displays because of Windows not properly colour managing OS wide, so stuff made for the sRGB colour space ends up pretty overblown when in wide gamut. For that, I had planned to run the monitor in sRGB emulation mode as it appears that LG calibrate them fairly well these days. There're no issues with running a clamped gamut mode with regard to what we talked about, is there?
Chief Blur Buster wrote:
02 Jul 2020, 12:01
For you, the LG 38GN950 will be essentially plug-n-play for the majority of your apps. You might just need to do some minor per-app configuring as described (e.g. emulators etc).
With all this info I've been attempting to digest over the last few days, I'm not sure what specific per-app configuring you're referring to. Do you mean something like forcing VRR on older emulators that don't support fullscreen? I was under the impression that beyond this, having VRR active should basically just 'work' and everything would be smooth and essentially perfect. Perhaps I missed something.

I also came across this topic while looking for information on the subject, and it did bring up a couple of things I was wondering about. Previously in the thread, we discussed letting VRR take over handling of matching the refresh rate to the frame rate of the emulator. 60 frames = 60hz, 57 frames = 57hz, and so on.

The thread brings up an interesting point:
Now, why does it matter? Unfortunately, monitors might not look the same at all refresh rates, especially 144Hz monitors. Many VA monitors look darker at lower refresh rates, and nearly all monitors have their overdrive settings optimized for maximum refresh rates. As a result, you may have two issues with adaptive sync at lower refresh rates:
  • Brightness flickering (when the monitor is rapidly switching between high and low refresh rates)
  • Ghosting/overshoot (trailing behind moving objects)
Now I'm not sure how the 38GN950 will perform in this regard as there are no professional reviews out from the usual suspects thus far, but it is the second bullet point I am more interested in. The first point is one we addressed previously: stable frame times lead to stable VRR, and rapid oscillation of frames may result in perceived brightness flickering (I've heard this is common in game loading screens as the fps can typically drop rapidly). This is basically game and software dependent though, and not a fault of the monitor, as far as I'm aware - as long as it is properly certified.

The second one regarding overdrive configuration - as these monitors are not using GSYNC modules (which have variable overdrive), and don't appear to have gone the extra mile to implement a Freesync based overdrive (like Nixeus has done), would it not stand to reason that the pixel response time would be worse at say, a VRR of 50/60Hz when using an emulator? You mentioned earlier that frame doubling wouldn't do anything on a sample and hold display in terms of lag and is redundant when we are utilising VRR: does this still apply when taking overdrive into account?

Thanks for the detailed responses so far, by the way. Fascinating stuff, even if it is taking some time to properly digest. Hope I'm making sense thus far.

lc155
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Joined: 30 Jun 2020, 21:15

Re: Some Freesync Questions

Post by lc155 » 04 Jul 2020, 09:28

So it turns out that the 38GN950 doesn't have the 1ms MBR, despite advertising it as a feature set on LG's website. Just saw a video of someone going through the monitor OSD.

Guess I won't need to worry about that part after all, then! Higher Hz it is.

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