Adaptive VSync vs Adaptive Vsync + FPS limit

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Meylink
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Re: Adaptive VSync vs Adaptive Vsync + FPS limit

Post by Meylink » 16 Jul 2021, 10:21

From all the games that I've tested ( Cyberpunk 2077, AC Valhalla, Horizon Zero Dawn ..), none drops to 30 fps and the fps usually around 45 to 60 fps with VSync On. I assume they're using Triple Buffering Vsync instead of double buffering (?)

Would it be better to use in this instance Adaptive Vsync or VSync with the low lag method? Of course, I could just lower the graphic settings to get a constant 60 fps but I'm wondering what's the best motion/performance between the two in that case.

Thanks again! You've been a heap of knowledge from all your contributions to the forums. I definitely learned a lot.

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RealNC
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Re: Adaptive VSync vs Adaptive Vsync + FPS limit

Post by RealNC » 17 Jul 2021, 03:13

Meylink wrote:
16 Jul 2021, 10:21
From all the games that I've tested ( Cyberpunk 2077, AC Valhalla, Horizon Zero Dawn ..), none drops to 30 fps and the fps usually around 45 to 60 fps with VSync On. I assume they're using Triple Buffering Vsync instead of double buffering (?)
Maybe. Maybe not. It's not a given that you'll get 30FPS. It used to be a given in the past, but now in modern rendering pipelines, the game might still be able to prepare the next frame for rendering even if the thread that did the frame presentation is blocked by vsync. When things happen asynchronously, then it's hard to tell what exactly will happen.

I suspect it depends on whether or not it's the GPU that takes more than 16.7ms to render a frame, or it's a combined GPU+CPU time. If the GPU took 14ms for example, and the CPU took 4ms, then even though that exceeds 16.7 total, it might not result in 30FPS. That's a guess though. I'm not an expert when it comes to rendering pipelines.
Would it be better to use in this instance Adaptive Vsync or VSync with the low lag method? Of course, I could just lower the graphic settings to get a constant 60 fps but I'm wondering what's the best motion/performance between the two in that case.
It depends on whether or not tearing is OK for you and whether or not the game you're playing drops to 30FPS. I can't stand tearing, so what I would do is use fast sync with the low lag FPS cap. Not vsync, nor adaptive vsync.
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Meylink
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Re: Adaptive VSync vs Adaptive Vsync + FPS limit

Post by Meylink » 17 Jul 2021, 06:50

I get tearing if I use it with FastSync. So I guess I'm just picking between different bad solutions : if I use VSync, below refresh rate, I feel like there's some kind of judder + the input lag / using adaptive Vsync, again below refresh rate, there's screen tearing but no input lag albeit when it's above there's input lag.

All in all the only solution is to bring out the wallet and get a VRR monitor. Anyhow, I still learned a lot from all these testings and I want to thank you again for taking time to answer my noob questions!

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Re: Adaptive VSync vs Adaptive Vsync + FPS limit

Post by RealNC » 17 Jul 2021, 06:55

Meylink wrote:
17 Jul 2021, 06:50
I get tearing if I use it with FastSync.
Fast sync has no tearing. So something isn't working right.
All in all the only solution is to bring out the wallet and get a VRR monitor.
Yeah. That's true. After I switched to a g-sync monitor, I never had to deal with any of that again. Before that, I would even add custom refresh rates (like 90Hz and 80Hz) that I can do a low latency FPS cap at 90 or 80FPS for games that struggled to go higher than that. Now it's easy. Just enable g-sync and cap FPS to whatever I please :mrgreen: No lag, no tearing, no FPS/Hz mismatch jitter.
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Meylink
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Re: Adaptive VSync vs Adaptive Vsync + FPS limit

Post by Meylink » 17 Jul 2021, 16:59

Yeah if I use FastSync with the low lag method, I do get a tearing line moving up and down when the fps is near the refresh rate. I did notice tho as soon as I drop fps to ~50 fps the tear line goes away. Note I'm using the frame color indicator ( 2 bars ) in Rivatuner.

So I overclocked the monitor to 75 Hz and set a frame cap of 60 fps with Fast Sync, and for some reason I no longer get any kind of screen tearing and there's basically no input lag. But then again the motion isn't as good as Vsync at 60 Hz.

Edit : Well, I guess I'm just spitting nonsense here, seems like Fast Sync doesn't work in DX12 games but only on DX11 and below ones. The low lag method with FastSync does work indeed in that case but it introduces some stutters. The testings above on DX12 games are basically locking the fps to 60 fps.

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