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; labeled “Max Frame Rate,” it 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 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 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 Inspector: 2> Frame Delay

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

Nvidia 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 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: <1 Frame Delay

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

To set a framerate limit, navigate to the “Manage 3D settings” section in the NVCP, locate the “Max Frame Rate,” entry, select “On,” set the desired limit, select “OK,” and finally select the “Apply” button after it appears in the lower right corner of the NVCP window.



3105 Comments For “G-SYNC 101”

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BlurryAlienGoZ00mXD
Member
BlurryAlienGoZ00mXD

If I change Vertical sync to “On” in “Manage 3D settings”, it forces “Adjust image settings with preview” from “Let the 3D application decide” to “Use the advanced 3D image settings“.

Ideally I don’t want this as I don’t want any artificial enhancements on my game, but it seems impossible to have both at the same time.

It’s not mentioned in the guide that it does this. Any advice / insight for this? Best to set as much of the “enhancing” “Manage 3D settings” (for example: “Antialias – Gamma correction”) to “Off” to make it is as close to “Let the 3D application decide” as possible?

Let me know if I’m misunderstanding. Thanks.

dandyjr
Member
dandyjr

Hello there! I recently bought a 500Hz G-sync monitor and it’s the first time I’ve owned a true G-sync monitor with a module. The exact model is the AW2524H. One of the first things I noticed with this monitor is that the frames never hit the max range of the monitor as if the module has it’s own way to prevent leaving the G-Sync range. The monitor is technically a 480Hz panel but it has a factory overclock you can set to 500Hz. In stock form (with all of the proper G-sync settings in the control panel) the frames automatically are capped at 477 and never will hit 480. Overclocked to 500Hz, The frames will never go above 496. I tested multiple games just to make sure and they all produced the same results. What I’m wondering is if this is an effect of this specific model or if this is true for all G-Sync native monitors. Does this mean that I never have to cap my fps because the monitor won’t allow the frames to hit the ceiling anyway? I noticed that if I enable reflex in supported games, the frames will be capped at 438 instead of 496. My guess is that Nvidia set such a low limit to be safe for G-Sync compatible monitors that happen to be 500Hz (since I’ve heard they are less accurate and will leave range more often). What are your thoughts on this? I’d be stoked to hear that I don’t have to cap my fps anymore but it seems too good to be true haha!

IggyRex
Member
IggyRex

Hello, you probably get asked this a lot, but I game on a lg c1 at 120hz, and I was wondering what would be best for my setup. I am currently using Vsync – on in the control panel, but I am unsure if I should set low latency to ultra or if setting to On would be the better option for me. Having it set to ON would require me to set an fps limit on a game basis correct? So something like elden ring would work better being capped to 59 or 57fps as opposed to it set to ultra which would do it for me. What are the benefits of either option? Sorry, and please let me know. I just want to get the most out of my hardware and out of gsync.

Kaffik
Member
Kaffik

Hi!
I have 165 Hz G-Sync Compatible (ls27ag500nuxen) monitor.
I used all your tips for this type of display but something irritates me a lot.
60 fps on my screen looks like 30-35 at best, I need to have like 95-100 fps to make it look like smooth 60.
For example my boyfriend has 144 Hz VRR TV and 60 fps looks like 60 fps.
I have DP 1.4 and VRR on.
Do I really need a G-Sync module to make it better?

Indignified
Member
Indignified

Hello, is there any point of having gsync or reflex on if fps is uncapped?

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