Question Is my understanding of "Fast Sync" correct ?

[anjris]

Hi All

I have a 60Hz OLED Tv and I am using "Fast Sync" for particular game

Why MSI benchmark is constantly showing 120FPS ?

Is "Fast Sync" supposed to match the frame rate as per monitor refresh rate and drop the excess frames into Bin ?

Is my understanding correct?

 

[anjris]

Vsync definitely introduces input lag even with it's supposed G-Sync Ultimate implementation, the input lag is crazy at 60Hz.

Fast Sync on the other hand is a decent choice for fighting screen tearing, and it has very minimal impact to input lag. I'm personally using Fast Sync since V-Sync off and G-Sync on still has screen tearing.

Thank you for your opinion

But this doesn't answer my original question.

 

[TerryLaze]

Hi All

I have a 60Hz OLED Tv and I am using "Fast Sync" for particular game

Why MSI benchmark is constantly showing 120FPS ?

Is "Fast Sync" supposed to match the frame rate as per monitor refresh rate and drop the excess frames into Bin ?

Is my understanding correct?

Fast sync doesn't do any frame limiting on its own, if your game is limited to 120FPS then it's from the game itself or from some other setting inside of windows or the nvidia control panel.
Fast sync just doesn't wait for both the frame and the display to be ready at the same time, instead it throws a frame to the display whenever the display is ready to show one.
Full sync or classic vsync would wait for a new frame and for the display to be ready, which is why it adds more lag.

 

[anjris]

Fast sync doesn't do any frame limiting on its own, if your game is limited to 120FPS then it's from the game itself or from some other setting inside of windows or the nvidia control panel.
Fast sync just doesn't wait for both the frame and the display to be ready at the same time, instead it throws a frame to the display whenever the display is ready to show one.
Full sync or classic vsync would wait for a new frame and for the display to be ready, which is why it adds more lag.

If I reiterate in simple words

My tv refresh rate is 60hz but fast vsync will generate according to gpu power irrespective of tv refresh rate

In my case its generating 120 fps but out of 120 fps its throwing 60 fps into garbage
And rest 60 frames it is displaying to tv with minimal latency
Did I understand correctly?

 

[BFG-9000]

FastSync mode really only works well when the card is capable of rendering at multiple times the refresh rate, like 3x. Unlike Adaptive which pauses GPU frames in a buffer using regular vSync when faster than refresh, here all frames are rendered but only the latest one is sent to the screen--this consumes a lot more power but input lag at least doesn't jitter all over the place (unless if only slightly above refresh, the most recent rendered frame is exactly the same as it would be in vSync with the same lag problem). Both of these disable framerate control if fps falls below refresh so the tearing will notify you whenever this happens.

FastSync showed up with the first Pascal drivers and is equivalent to AMD's Enhanced Sync

 

[anjris]

Thank you. I grabbed your point now.

Generally fast vsync will use in online gaming where gpu frames are rendering at multiple times than refresh rate where we need minimal input lag.

If we see same case for campaign games. Then normal vsync would work with 59 fps theory. Normal input lag won't be noticeable in story/campaign games