Blur Buster's G-SYNC 101 Series Discussion

Talk about NVIDIA G-SYNC, a variable refresh rate (VRR) technology. G-SYNC eliminates stutters, tearing, and reduces input lag. List of G-SYNC Monitors.
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jorimt
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Re: Blur Buster's G-SYNC 101 Series Discussion

Post by jorimt » 21 Sep 2017, 09:35

ViTosS wrote:Hey guys, I have a question, the optimal way for the less input lag at the moment is still G-Sync ON and V-Sync ON in NVCP, right? But why I have to set framerate limit in RTSS to 141fps (144hz) if the V-Sync ON at NVCP is already putting my FPS limit ingame to 144fps? Do I need RTSS limit too? Thank you!
The framerate limit is to keep G-SYNC within its range, and thus prevent it from hitting or exceeding the G-SYNC ceiling, at which point G-SYNC acts like V-SYNC and introduces several frames of delay.

I suggest using a -2 or -3 in-game framerate limit if the game contains a framerate limiter, and RTSS if not (in-game limiters provide lower latency than RTSS; complete details are already available in my article [which this thread is based on the discussion of], as are the answers to your original question).
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Author: Blur Busters "G-SYNC 101" Series

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Re: Blur Buster's G-SYNC 101 Series Discussion

Post by ViTosS » 21 Sep 2017, 09:48

jorimt wrote:
ViTosS wrote:Hey guys, I have a question, the optimal way for the less input lag at the moment is still G-Sync ON and V-Sync ON in NVCP, right? But why I have to set framerate limit in RTSS to 141fps (144hz) if the V-Sync ON at NVCP is already putting my FPS limit ingame to 144fps? Do I need RTSS limit too? Thank you!
The framerate limit is to keep G-SYNC within its range, and thus prevent it from hitting or exceeding the G-SYNC ceiling, at which point G-SYNC acts like V-SYNC and introduces several frames of delay.

I suggest using a -2 or -3 in-game framerate limit if the game contains a framerate limiter, and RTSS if not (in-game limiters provide lower latency than RTSS; complete details are already available in my article [which this thread is based on the discussion of], as are the answers to your original question).
Thank you, but I didn't find in the article telling why to use RTSS together with V-Sync, but if the limit of G-Sync for my monitor is 144fps, I still don't get why I need the RTSS to limit what is already limited to 144fps (V-Sync ON). Just one more question I promise, if I disable G-Sync and have my framerates all unlocked, I would have better input lag than when using G-Sync + V-Sync + RTSS limit? Because I really can't see the screen tearing with G-Sync being ON or OFF, so all I want is the less possible input lag.

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Re: Blur Buster's G-SYNC 101 Series Discussion

Post by jorimt » 21 Sep 2017, 11:36

ViTosS wrote:Thank you, but I didn't find in the article telling why to use RTSS together with V-Sync, but if the limit of G-Sync for my monitor is 144fps, I still don't get why I need the RTSS to limit what is already limited to 144fps (V-Sync ON).

Simple, if you don't use a framerate limiter, and your framerate hits or exceeds your maximum refresh rate with G-SYNC, it reverts to V-SYNC input lag levels with G-SYNC + V-SYNC "On" (or starts to tear constantly with G-SYNC + V-SYNC "Off"):

Image

At 144Hz or higher, G-SYNC can no longer adjust the refresh rate to the framerate, and thus it reverts to normal V-SYNC behavior. A framerate limit keeps it within the G-SYNC range.
ViTosS wrote:Just one more question I promise, if I disable G-Sync and have my framerates all unlocked, I would have better input lag than when using G-Sync + V-Sync + RTSS limit? Because I really can't see the screen tearing with G-Sync being ON or OFF, so all I want is the less possible input lag.
G-SYNC + V-SYNC "Off" vs. G-SYNC + V-SYNC "On" at 144Hz:

Image

At 144Hz, you're saving a maximum of 2ms with G-SYNC + V-SYNC "Off" over G-SYNC + V-SYNC "On," and that savings is directly reflected in the tearline. That's only for first reaction. If we measure at crosshair level, the input lag difference between the two methods is virtually zero.

If you don't care about tearing at all, then don't use G-SYNC. Simply disable G-SYNC and V-SYNC, and don't set an FPS limit with anything. If you can sustain very high framerates at 144Hz, you'll have the least input lag possible with that configuration:

Image
(jorimt: /jor-uhm-tee/)
Author: Blur Busters "G-SYNC 101" Series

Displays: ASUS PG27AQN, LG 48CX VR: Beyond, Quest 3, Reverb G2, Index OS: Windows 11 Pro Case: Fractal Design Torrent PSU: Seasonic PRIME TX-1000 MB: ASUS Z790 Hero CPU: Intel i9-13900k w/Noctua NH-U12A GPU: GIGABYTE RTX 4090 GAMING OC RAM: 32GB G.SKILL Trident Z5 DDR5 6400MHz CL32 SSDs: 2TB WD_BLACK SN850 (OS), 4TB WD_BLACK SN850X (Games) Keyboards: Wooting 60HE, Logitech G915 TKL Mice: Razer Viper Mini SE, Razer Viper 8kHz Sound: Creative Sound Blaster Katana V2 (speakers/amp/DAC), AFUL Performer 8 (IEMs)

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Re: Blur Buster's G-SYNC 101 Series Discussion

Post by ViTosS » 21 Sep 2017, 17:09

jorimt wrote:
ViTosS wrote:Thank you, but I didn't find in the article telling why to use RTSS together with V-Sync, but if the limit of G-Sync for my monitor is 144fps, I still don't get why I need the RTSS to limit what is already limited to 144fps (V-Sync ON).

Simple, if you don't use a framerate limiter, and your framerate hits or exceeds your maximum refresh rate with G-SYNC, it reverts to V-SYNC input lag levels with G-SYNC + V-SYNC "On" (or starts to tear constantly with G-SYNC + V-SYNC "Off"):

Image

At 144Hz or higher, G-SYNC can no longer adjust the refresh rate to the framerate, and thus it reverts to normal V-SYNC behavior. A framerate limit keeps it within the G-SYNC range.
ViTosS wrote:Just one more question I promise, if I disable G-Sync and have my framerates all unlocked, I would have better input lag than when using G-Sync + V-Sync + RTSS limit? Because I really can't see the screen tearing with G-Sync being ON or OFF, so all I want is the less possible input lag.
G-SYNC + V-SYNC "Off" vs. G-SYNC + V-SYNC "On" at 144Hz:

Image

At 144Hz, you're saving a maximum of 2ms with G-SYNC + V-SYNC "Off" over G-SYNC + V-SYNC "On," and that savings is directly reflected in the tearline. That's only for first reaction. If we measure at crosshair level, the input lag difference between the two methods is virtually zero.

If you don't care about tearing at all, then don't use G-SYNC. Simply disable G-SYNC and V-SYNC, and don't set an FPS limit with anything. If you can sustain very high framerates at 144Hz, you'll have the least input lag possible with that configuration:

Image
Thank you for the explanation, but I still don't get the part where I bold the text, how is my framerate going to exceed 144fps with G-Sync if I'm using V-Sync too? It will be always 143~144fps.

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Re: Blur Buster's G-SYNC 101 Series Discussion

Post by jorimt » 21 Sep 2017, 20:45

Because V-SYNC doesn't stop frames from rendering above your refresh rate, it only limits delivery of frames to up to 144 times a second at 144Hz, so if your framerate exceeds that limit internally (this does not reflect in FPS counters), the buffers begin to get backed up, which delays delivery of frames on-screen, and thus adds extra input lag.

A framerate limit slightly below the refresh rate prevents this over-queuing of buffers, both for G-SYNC and standalone V-SYNC, as it, unlike V-SYNC, stops frames from rendering above that set limit.
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Author: Blur Busters "G-SYNC 101" Series

Displays: ASUS PG27AQN, LG 48CX VR: Beyond, Quest 3, Reverb G2, Index OS: Windows 11 Pro Case: Fractal Design Torrent PSU: Seasonic PRIME TX-1000 MB: ASUS Z790 Hero CPU: Intel i9-13900k w/Noctua NH-U12A GPU: GIGABYTE RTX 4090 GAMING OC RAM: 32GB G.SKILL Trident Z5 DDR5 6400MHz CL32 SSDs: 2TB WD_BLACK SN850 (OS), 4TB WD_BLACK SN850X (Games) Keyboards: Wooting 60HE, Logitech G915 TKL Mice: Razer Viper Mini SE, Razer Viper 8kHz Sound: Creative Sound Blaster Katana V2 (speakers/amp/DAC), AFUL Performer 8 (IEMs)

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Re: Blur Buster's G-SYNC 101 Series Discussion

Post by Sparky » 21 Sep 2017, 21:35

ViTosS wrote: Thank you for the explanation, but I still don't get the part where I bold the text, how is my framerate going to exceed 144fps with G-Sync if I'm using V-Sync too? It will be always 143~144fps.
Say you have a store, and the cashier can check out one person every minute. You can still have several people waiting in line for the person in front to get checked out. If you prevent people from entering the store faster than once per minute, then the cashier can keep up with customers and the line at the cash register is short or empty. The principle of a framerate cap is similar, you're preventing excessive buffering, so the time between a user input and the consequence of that input on screen is lower.

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Re: Blur Buster's G-SYNC 101 Series Discussion

Post by RealNC » 22 Sep 2017, 00:57

ViTosS wrote:Thank you for the explanation, but I still don't get the part where I bold the text, how is my framerate going to exceed 144fps with G-Sync if I'm using V-Sync too? It will be always 143~144fps.
VSync makes sure you don't get tearing while the monitor is running within the g-sync refresh rate range. The frame limiter will make sure the monitor stays within the g-sync range.

If the game runs at 144FPS, you are NOT within the g-sync range.
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Re: Blur Buster's G-SYNC 101 Series Discussion

Post by sekta » 22 Sep 2017, 01:32

Anyone kind enough to post a list of games where it is BETTER to use RTSS instead of the ingame limiter?

At the moment I play CS:GO, CoD series, PUBG, Osu!. These all have their own limiters, which I use, I only use RTSS for CoD BO2 since that caps at 120 or 200 fps.

CS:GO and CoD limiters are all over the place though, CoD's fps limiter seems to cap in ranges (Quake Live, exactly the same) on any OS after Windows 7, like setting to a value between 126 and 142 will result in the same fps limit of 135-138, a value of 200 will result in a cap of around 180 fps.

So I'm not sure if RTSS would actually be better in these cases.

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Re: Blur Buster's G-SYNC 101 Series Discussion

Post by RealNC » 22 Sep 2017, 03:25

For CS:GO you want the in-game limiter (fps_max). For the others, I don't know.

I don't know why CS:GO is all over the place for you. It isn't for anyone else.
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Re: Blur Buster's G-SYNC 101 Series Discussion

Post by Sparky » 22 Sep 2017, 09:01

sekta wrote:Anyone kind enough to post a list of games where it is BETTER to use RTSS instead of the ingame limiter?

At the moment I play CS:GO, CoD series, PUBG, Osu!. These all have their own limiters, which I use, I only use RTSS for CoD BO2 since that caps at 120 or 200 fps.

CS:GO and CoD limiters are all over the place though, CoD's fps limiter seems to cap in ranges (Quake Live, exactly the same) on any OS after Windows 7, like setting to a value between 126 and 142 will result in the same fps limit of 135-138, a value of 200 will result in a cap of around 180 fps.

So I'm not sure if RTSS would actually be better in these cases.
If the game has an in game limiter, using it will be the lowest latency option. RTSS has one more frame of buffering when compared to an in game limiter, which in some cases can reduce stutter. That's a tradeoff judgment you'll have to make on a case by case basis. As far as I'm aware, RTSS is the best external framerate available.

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