Polling behavior of Gsync and input lag

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Blurlight
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Polling behavior of Gsync and input lag

Post by Blurlight » 29 Apr 2024, 12:56

http://www.blurbusters.com/gsync/preview2/

That is an old article, but very shocking.
I am not familiar with the technical knowledge or the latest news, so I don't know how things have changed since this article was written.
Namely, whether Nvidia improved the input lag due to Gsync polling when above the limited frame rate.
Can someone please enlighten me on this?

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RealNC
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Re: Polling behavior of Gsync and input lag

Post by RealNC » 29 Apr 2024, 13:18

Blurlight wrote:
29 Apr 2024, 12:56
http://www.blurbusters.com/gsync/preview2/

That is an old article, but very shocking.
I am not familiar with the technical knowledge or the latest news, so I don't know how things have changed since this article was written.
Namely, whether Nvidia improved the input lag due to Gsync polling when above the limited frame rate.
Can someone please enlighten me on this?
There is nothing to improve. G-sync adapts the display to the game's frame rate. It can't magically overclock your display to drive it past its max refresh rate. The polling can be disabled by setting vsync OFF.

This is why both Nvidia Reflex and control panel Ultra Low Latency will cap FPS well below max Hz.
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Blurlight
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Re: Polling behavior of Gsync and input lag

Post by Blurlight » 29 Apr 2024, 13:55

Thank you for your answer.

1. so you are saying that even with Gsync now, if Vsync and Nvidia Reflex were turned off, a 143fps limit on a 144hz monitor would increase input lag somewhat significantly compared to Gsync off, like the results on CSGO in this article?

This article explains that when Gsync is capped out at the maximum refresh rate, it waits for screen updates just like Vsync.
2. Is this because Vsync is turned on?
3. or is this a problem specific to Gsync?

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Re: Polling behavior of Gsync and input lag

Post by RealNC » 30 Apr 2024, 09:20

When this article was written, Nvidia had not introduced the option yet to set vsync to OFF. So all the measurements were with vsync ON, which of course will increase latency if you don't cap FPS well below Hz.
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Re: Polling behavior of Gsync and input lag

Post by Blurlight » 30 Apr 2024, 09:35

Very polite and concise reply.
I appreciate it. Thank you very much.

abdelkadr13
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Re: Polling behavior of Gsync and input lag

Post by abdelkadr13 » 01 May 2024, 18:29

RealNC wrote:
30 Apr 2024, 09:20
When this article was written, Nvidia had not introduced the option yet to set vsync to OFF. So all the measurements were with vsync ON, which of course will increase latency if you don't cap FPS well below Hz.
Do you mean vsync off via Nvida or the Game?

Normally Nvidia's standard settings is to let the game decide and when its turned off there, there shouldnt be problems, right?
Or should we make sure to turn vsync off in nvidia also?

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Re: Polling behavior of Gsync and input lag

Post by RealNC » 02 May 2024, 08:34

abdelkadr13 wrote:
01 May 2024, 18:29
Do you mean vsync off via Nvida or the Game?

Normally Nvidia's standard settings is to let the game decide and when its turned off there, there shouldnt be problems, right?
Or should we make sure to turn vsync off in nvidia also?
It didn't matter. Vsync was always enabled when g-sync first released, regardless of what in-game or NVCP settings were used. I took a few driver releases until it was possible to run g-sync without vsync.
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Re: Polling behavior of Gsync and input lag

Post by abdelkadr13 » 02 May 2024, 15:04

RealNC wrote:
02 May 2024, 08:34
abdelkadr13 wrote:
01 May 2024, 18:29
Do you mean vsync off via Nvida or the Game?

Normally Nvidia's standard settings is to let the game decide and when its turned off there, there shouldnt be problems, right?
Or should we make sure to turn vsync off in nvidia also?
It didn't matter. Vsync was always enabled when g-sync first released, regardless of what in-game or NVCP settings were used. I took a few driver releases until it was possible to run g-sync without vsync.
Okay I understand. But now if i dont want vsync to be on, is it enough to disable it ingame or should i also disable it via NVCP?

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Re: Polling behavior of Gsync and input lag

Post by RealNC » 03 May 2024, 11:44

abdelkadr13 wrote:
02 May 2024, 15:04
Okay I understand. But now if i dont want vsync to be on, is it enough to disable it ingame or should i also disable it via NVCP?
If NVCP is set to "application controlled" then it's gonna be OFF if you disable it in the game.
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