Questions about G-Sync

First off, I'm playing RPGs, strategy games, etc that do not require high frame rates. However, I always set IQ to the highest setting so the GPU is always taxed.

As I understand it, the benefit of G-Sync is that it adapts your refresh rate to your fps.

However, this means that if I play a game like the Witcher 3 I never benefit from my 144hz screen as it will adapt to typically 60-80 fps I get at ultra settings.

But, you'll say, G-Sync still has a benefit because it constantly adapts to your fps, so there won't be any tearing.

Yet, what if lock my fps to 48 fps (which will remain constant throughout play whatever the load) and disable G-Sync. 48fps is 1/3 of 144hz so screen refresh and fps will stay in sync, I won't see any tearing, and I'll have the benefit of my 144hz screen. For less demanding games I could lock fps at 72fps (1/2 144hz). Is this correct?

 

You can use Nvidia Profile Inspector to set VSync to 1/2 refresh rate (72 FPS) or 1/3 refresh rate (48 FPS) and that will also eliminate tearing, however it will increase input lag substantially due to the nature of VSync.

 

You could dry adaptive vsync which only takes effect if the frame rate exceeds your refresh rate, which is where the tearing occurs usually.

 

What do you call "benefit of 144 Hz"? lol The benefit of a 144Hz is that if your GPU can render the video game as high as 144 fps you'll be able to get a more fluid/smooth motion image.

What vsync does? Well it prevent the screen tearing. Screen tearing happens any time that the GPU sends a number of frames per second different than the refresh rate of the screen (the screen Hz).

So if you enable vsync and your GPU is not able to achieve 144 fps, then the GPU will render at half refresh rate fps, or a third , of a fourth etc

The magic of G-Sync is that it will adapt your screen refresh rate to whatever your GPU is able to obtain. So you'll always get a motion image at the highest frame rate that you GPU is able to get but screen tearing free.

 

Why not just capping fps with rtss? You only have tearing when fps and refresh rates are out of sync.

 

Capping FPS doesn’t sync FPS and refresh rate, it only chops the top off the frame rate.

 

You also see the difference between 144hz vs 60hz in 2D. It's easier on the eyes. I know what gsync and vsync do. The point is that I want the smoothness of 144hz with lower fps.

 

Yes, but if you have a constant 1 frame for each two or three refresh cycles, would that not eliminate tearing as well? I've tried it and it looks smooth to me.

 

That’s exactly what 1/2 and 1/3 refresh rate VSync do.

 

But how smooth a video is, is not related to the refresh rate of the screen yet to the fps of the source material. For example if you play a 15 fps video on a 120 Hz screen you'll see a stuttering video no matter what software trick you use (although the screen and the GPU will be on sync so there will be no screen tearing). Technically speaking the only way you get the "smoothness of 144 Hz" is with a video source of at least 144 fps. In my opinion though I see no improvement over 90+fps in video games. Some guys say that they get better input lag with higher fps also, but I don't play video games that require that kind of fast time response.

 

It doesn't work like this.

 

So the error in my reasoning is that I thought capping fps did the same thing as vsync. Thanks for pointing that out. Will just continue to use G-Sync then...

 

I've noticed that even with G-Sync enabled capping fps might help. Sometimes due to poor optimization in games, for no apparent reason you get a frame rate drop from let's say from 144 to 120 fps, G-Sync will prevent from getting screen tearing and still going with a high frame rate, but that little fps drop will cause a perceptible micro stutter. If in that particular scenario your fps were capped to 120 fps you'll not perceive the micro stutter and you'll have a smoother experience. Of course some games are so badly optimized (like Jedi Fallen Order) that in some occasions I go from 90 fps to 60 fps in one particular location, if I cap to 60 fps in the same particular location the frame rate now drops from 60 to 30 fps, that's just a bug not a hardware bottleneck.

 

Also make sure you enable VSync and limit FPS to 3 frames below the refresh rate, as that is the correct way to setup G-Sync.

 

I concur. My previous laptop had G-Sync and it was best to set it a frame or so below the panel refresh.

 

Curious, what benefit does dropping it a frame below the refresh rate have?

 

It’s because you have to enable VSync when using G-Sync as this activates frametime compensation to prevent tearing at the upper and lower bounds of the variable refresh rate window. If you don’t limit FPS to at least 2-3 frames below the refresh rate (1 frame is not enough), you’ll just be using VSync instead of G-Sync, and be hit with the full VSync input lag, since G-Sync only works below the refresh rate.

 

unless your getting more than 144fps there is absolutely no reason to avoid g sync end of story