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So my monitor has a setting that enables you to view the current refresh rate in real-time, and when you have free-sync off it really doesn't do anything of note; it just sits there at 144Hz the whole time. However, when I turn FreeSync on, it's quite weird. I play a game at 140fps, locked in RTSS with nearly flawless unchanging frame-time as shown by the RTSS frame-time graph, and yet the current refresh rate is just bouncing around dozens of times a second and seems to bounce around in a range from like 130-140. What's also strange is that a 60fps game plays only at a refresh rate range of like 55-65 (and sometimes during pausing or loading screen it will jump rapidly to max refresh rate then immediately fall down) instead of just doubling that when my monitor can support it. However, what's even more strange is that it will double, quadruple, or even greater the refresh rate if I set it in RTSS to 40 fps or even 15fps. So effectively my refresh rate is much higher at 15fps than it is at 60fps lol. But when I turn Free-Sync off, my monitor is at max refresh rate even for 60fps.

So my questions are:

1) Why does my refresh rate increase more with lower fps content than with 60fps content when I clearly have the max refresh rate to be able to do it at 120Hz+?
2) Why is the refresh rate fluctuating so rapidly when the frametime is near flawless? And it's not even like it's rapidly fluctuating between 139-141, it seems to fluctuate across a pretty large range (although it's hard to tell because it updates so rapidly)
3) Is 60fps gaming on a display that is 120Hz+ any benefit if you have FreeSync enabled, since it's essentially just 60fps @ 60Hz, except (possibly) even less stable?
4) Why would I not just turn Free Sync off if I'm able to get a steady framerate, as this would remove the small amount of input latency from VRR, would allow me to receive the full benefits of 60fps @ 120Hz, and have no screen tearing as the frame-rate is not dipping? Is there something I am missing here?
5) Is this concept related to why many high refresh-rate monitors seem to have more input latency at 60Hz VRR than lower refresh-rate monitors? On rtings, you can view input latency at 60Hz VRR and almost all of the monitors best in that category are either 60Hz, 75Hz, 120Hz, or 144Hz. No 240Hz or 360Hz monitors seem to do as well in this category.

Thanks for any insight into this.

Albatross17 wrote: ↑

15 Aug 2021, 15:15

So my monitor has a setting that enables you to view the current refresh rate in real-time, and when you have free-sync off it really doesn't do anything of note; it just sits there at 144Hz the whole time. However, when I turn FreeSync on, it's quite weird. I play a game at 140fps, locked in RTSS with nearly flawless unchanging frame-time as shown by the RTSS frame-time graph, and yet the current refresh rate is just bouncing around dozens of times a second and seems to bounce around in a range from like 130-140.

That meter isn't reliable or accurate. The only thing it's useful for determining is if VRR is engaged in the given game; if it is, the meter will fluctuate, if it isn't, the meter will remain static.

Try using this RTSS add-on instead:
https://forums.guru3d.com/threads/does- ... st-5823497

I've never attempted to use it with FreeSync, just G-SYNC/G-SYNC Compatible, but it should work regardless.

As for the doubling you're seeing, that is LCF (low framerate compensation), or what I called the "Minimum Refresh Range" in my article:
https://blurbusters.com/gsync/gsync101- ... ettings/2/

Once the framerate reaches the approximate 36 and below mark, the G-SYNC module begins inserting duplicate refreshes per frame to maintain the panel’s minimum physical refresh rate, keep the display active, and smooth motion perception. If the framerate is at 36, the refresh rate will double to 72 Hz, at 18 frames, it will triple to 54 Hz, and so on. This behavior will continue down to 1 frame per second.

Regardless of the reported framerate and variable refresh rate of the display, the scanout speed will always be a match to the display’s current maximum refresh rate; 16.6ms @60Hz, 10ms @100 Hz, 6.9ms @144 Hz, and so on. G-SYNC’s ability to detach framerate and refresh rate from the scanout speed can have benefits such as faster frame delivery and reduced input lag on high refresh rate displays at lower fixed framerates (see G-SYNC 101: Hidden Benefits of High Refresh Rate G-SYNC).

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Albatross17 wrote: ↑

15 Aug 2021, 15:15

4) Why would I not just turn Free Sync off if I'm able to get a steady framerate, as this would remove the small amount of input latency from VRR, would allow me to receive the full benefits of 60fps @ 120Hz, and have no screen tearing as the frame-rate is not dipping? Is there something I am missing here?

VRR does not add input latency, it prevents tearing. The very act of tearing can create an appreciable input latency reduction with framerates far above the refresh rate, but then you're left with said artifact as a result.

As for what else you might be missing on this subject, you'd need to clarify if you're talking about G-SYNC on + V-SYNC on/off vs G-SYNC off + V-SYNC off, or G-SYNC on + V-SYNC on/off vs G-SYNC off + V-SYNC on?

Albatross17 wrote: ↑

15 Aug 2021, 15:15

5) Is this concept related to why many high refresh-rate monitors seem to have more input latency at 60Hz VRR than lower refresh-rate monitors? On rtings, you can view input latency at 60Hz VRR and almost all of the monitors best in that category are either 60Hz, 75Hz, 120Hz, or 144Hz. No 240Hz or 360Hz monitors seem to do as well in this category.

Many 240Hz+ monitors do scanout rate conversion to try and fit and/or stretch a 60Hz signal to the higher native max refresh rate of the display, creating additional delay. This penalty does not typically apply to 60 FPS (VRR mode or otherwise) with the monitor set to a 240Hz/360Hz physical refresh rate, however, only with a 240Hz/360Hz monitor forced to a physical 60Hz refresh rate.