G-SYNC 101: External FPS Limiter HOWTO


In-game vs. External Framerate Limiters*

*As of NVIDIA driver version 441.87, NVIDIA has made an official framerate limiting method available in the NVCP/App; labeled “Max Frame Rate,” which is a CPU-level FPS limiter, and as such, is comparable to the RTSS framerate limiter in both frametime performance and added delay. The “NVIDIA Profile Inspector: 2> Frame Delay” setup detailed further below is legacy, and does not apply to the “Max Frame Rate” limiter, the setup of which is also now detailed below it.

As described in G-SYNC 101: In-game vs. External FPS Limiters, In-game framerate limiters, being at the game’s engine-level, are almost always free of additional latency, as they can regulate frames at the source. External framerate limiters, on the other hand, must intercept frames further down the rendering chain, which can result in delayed frame delivery and additional input lag; how much depends on the limiter and its implementation.

In-game framerate limiters, however, aren’t available in every game, and while they aren’t required for games where the framerate can’t meet or exceed the maximum refresh rate, if the system can sustain the framerate above the refresh rate, and a said option isn’t present, an external framerate limiter must be used with G-SYNC to prevent V-SYNC-level input lag instead.

RTSS is a CPU-level FPS limiter, and introduces up to 1 frame of delay, whereas NVIDIA Profile Inspector uses a driver-level FPS limiter, which introduces 2 or more frames of delay. See G-SYNC 101: In-game vs. External FPS Limiters for complete details, along with input latency tests comparing the two external solutions against an in-game limiter.

RivaTuner Statistic Server: <1 Frame Delay

RTSS is available standalone here, or bundled with MSI Afterburner here.

If only a framerate limiter is required, the standalone download will suffice. MSI Afterburner itself is an excellent overclocking tool that can be used in conjunction with RTSS to inject an in-game overlay with multiple customizable performance readouts.

Blur Buster's G-SYNC 101: External FPS Limiter HOWTO

RTSS can limit the framerate either globally or per profile. To add a profile, click the “Add” button in the lower left corner of the RTSS windows and navigate to the exe. To set a frame limit, click the “Framerate limit” box and input a number.

NVIDIA Profile Inspector: 2> Frame Delay

An unofficial extension of the official NVIDIA Control Panel, NVIDIA Profile Inspector (download here) exposes many useful options the official control panel does not, including a driver-level framerate limiter.

The NVIDIA Profile Inspector can limit the framerate either globally or per profile (more details on profile creation can be found here).

To set a frame limit, locate the “Frame Rate Limiter” dropdown in the “2 – Sync and Refresh” section, select the desired limit, and then click the “Apply Changes” button in the upper right corner of the NVIDIA Inspector window.

Blur Buster's G-SYNC 101: External FPS Limiter HOWTO

As of NVIDIA Profile Profile Inspector version 2.1.3.6 and NVIDIA driver branch R381 or later, a new “Frame Rate Limiter Mode” dropdown has been introduced with a “Limiter V2 – Force Off” option:

Blur Buster's G-SYNC 101: External FPS Limiter HOWTO

This option claims to reduce the limiter’s input lag; exactly by how much, and with what combination of settings, remains to be determined.

NVIDIA Control Panel/App: <1 Frame Delay

As of NVIDIA driver version 441.87, NVIDIA has made an official framerate limiting method available in the NVIDIA Control Panel/App labeled “Max Frame Rate.”

To set a framerate limit, navigate to “Graphics” in the NVIDIA Ap or “Manage 3D settings” in the NVCP, locate “Max Frame Rate,” select “On,” set the desired limit, and select “Apply,” or “OK,” then “Apply.“



3867 Comments For “G-SYNC 101”

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tenki
Member
tenki

Hello,

Thank you for your amazing guide, I am always following it very carefully and it was for me an immense help.

I have some questions though because I think that my setup is not 100% optimized

I have a desktop MSI QD-Oled 360hz 1440p, but I switch the refresh rate to 120hz because I usually do not play games more than 120fps , and my desktop gaming have a 5080 GPU and 9859X3D Ryzen.

For my questions:

– In NVCP I have like your guide and I have have v-synch set to default, gsync on only for full screen and LLM off. In game I have for sure V-sync on. I have no idea if it is better to cap the frame rate to 116fps with NVCP or RTSS because sometimes in game I have frequently shutterings when I cap, no matter what game is. Should also be cause because LLM Is off?

– Based on the question before, I don’t understand when it is the case to enable the limiter in game. Should it be a slider or more like a selectable option ( 60fps, 120fps, uncapped etc). I usually have every time uncapped, but is there a certain rule for it?

– sometimes in games I go over 120fps and oscillates every time , but not reaching 120fps or less. Though when I cap, I even go down ( not stable) , how is that possible? Should I not cap

– OLED on 240hz is flickering so much with G-sync, this is another reason why I put 120hz, but if you suggest to put 240hz and that’s it let me know.

Thank you so much in advance and sorry for my long comment!

asari7k
Member
asari7k

im still a bit confused. so i want to play dbfz at the lowest latency possible bc its a fighting game capped at 60 fps and im playing on a 240hz monitor. so whats better g sync + v sync (in ncvp) on with low latency mode on ultra or just disable g sync and v sync but low latency stil on ultra . bc ive seen some videos on youtube that tested capped 60fps games at higher refres rate and it gives lower latency so when i use g sync is automaticly caps it at 60hz so doesnt that just completly ruin the g sync vs v sync setup ?

user2422
Member
user2422

Thanks for the comprehensive guide.

I have some questions on two topics:

1. If i have a 320Hz monitor with G-Sync enabled and play let’s say Apex Legends capped at 240 fps and can’t notice any obvious screen tearing, is there any reason to still use V-Sync in this scenario? From my understanding the latency in this scenario should be roughly the same whether V-Sync is enabled or disabled, so could it potentially have any other up or downsides? Also regarding this question, the increase in smoothness that is often shown with the optimal G-Sync configuration, is that due to the VRR or is it caused by the combination of G-Sync + V-Sync?

2. There seems to be a lot of situational use for some of these settings, so with all your knowledge and own personal experience over all those years now, what are you personally using when it comes to settings like LLM, Reflex, Windows VRR toggle, in-game vs driver V-Sync, what framerate limiters to use and what value to cap to?

Iriodus
Member
Iriodus

So, 2 separate but related questions:

1) For games that use the Vulkan renderer, like Doom Eternal, should we be using borderless fullscreen or exclusive fullscreen?

2) Not sure if you’d know the answer to this one, but since Proton on Linux uses a DirectX-to-Vulkan translation layer, should people use the recommendation for question 1 above, or say if a game is DirectX11 before taking into account the DX-to-Vulkan translation do use Fullscreen/Exclusive Fullscreen as if we were on Windows.

For reference, I’ve replicated the optimal G-Sync setup on my Linux machine, and since switching I’ve just been doing “If it’s originally DX11 or lower? Fullscreen/Exclusive Fullscreen. If it’s originally DX12? I use borderless fullscreen”

ksydew
Member
ksydew

Sorry for posting so much but I have one last question, I just bought the acer Nitro XV275U F5BIIPPRX, it’s a free sync premium Pro monitor but isn’t g sync certified. It should still work with g sync no problem right? I have it turned on same usual settings, g sync indicator is working and on in the top right corner, but just want to make sure it’s fine? It seems like it is but I’m not the expert

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