How exactly does G-Sync work?

[Flevor]

i have an acer predator XB271HK 4K 60hz with g-sync

 

I've been playing around with settings because i had several issues with screen lag and tearing in games because things weren't really smooth at all

 

I've turned on V-sync(Adaptive) in N-vidia controll panel and i put a cap on m FPS to 55 and guess what

 

screen lagg is all gone! is it supposed to work like this? i feel like my SLI GTX 1080 is going to waste like this...

[Enderman]

Are you talking about gsync or vsync?

[Zebedeeboing]

I think you mean turning on G Sync in the control panel? 

 

Turn on G Sync but you may need to turn off V sync within games. If you're having issues beyond that I can only imaging you are having other hardware issues/settings too high. If you have not already, make sure that your drivers are up to date. 

[Mira Yurizaki]

You're supposed to enable GSync in the NVIDIA Control Panel. I don't believe it's enabled by default. You're also supposed to turn off V-Sync. Adaptive VSync also turns on VSync if your frame rate exceeds the refresh rate and turns it off otherwise. However since you have a GeForce 10 card, you should leave it on Fast Sync since it effectively achieves the same thing while minimizing input lag.

 

Use NVIDIA's GSync demo to test your setup

[Flevor]

No,sorry i explained it a it wrong

 

G-sync is turned on correctly

 

with normal settings and V sync YES i mean V sync off in nvidia controll panel and my fps uncapped in games i get screen lag while playing fpses or mmos

 

with V-Sync(adaptive) turned on in nvidia control panel and i cap my fps too 55 or 60 i get no screen lagg or stutter in games and everything is smooth as hell

 

[Darkseth]

G-Sync is an Adaptive Refresh Rate (VRR).

It's a Technology, similar to Freesync, aka Adaptive Sync (from VESA), that is pretty much the opposite of V-Sync ( Vertical Sync).

 

First of all, V-Sync:

Monitor has 60 Hz, GPU is set to Monitor's Refresh Rate. Which means, 60 fps Limit max, and everything above, will stay at 60 fps. This is the optimum here. perfectly smooth 60 fps, with every single Image beein displayed for 16,67 ms duration.

If you fall BELOW 60 fps, THEN you have the Problem: Stuttering.

Imagine it as a simple Math problem. Monitor has 60 Hz, it refreshes 60 times per Second.

V.-Sync forces the GPU to "give" the Image only as a full one (no half-images, like when you have Tearing). As long the GPU is fast enough to render it in Time, everything is good (except maybe a bit Input Lag). If GPu is NOT fast enough, then the Monitor will display the Previous Image again --> It feels like that one image "freezes". It won't stay for 16,67 ms, but 33,4 ms (double as long).

This is stuttering.

50 fps and 60 Hz. How do you fit 50 images in 60 Hz? By doubling 10 of the 50, then you get 60.

 

Now G-Sync: Exactly the Opposite. The GPU pushes out frames, but the Monitor will match the GPU. If the GPU can only render 52 fps, the Monitor will run in 52 Hz.

If the GPU can render 38 fps, the Monitor will run in 38 fps. This changes in realtime without Delay.

This way, you will have no stuttering (because no doubled frames. Monitor refreshes as soon the GPU has the next Frame ready), and no Tearing (because it's "synced"). Also, Input Lag doesn't increase noticeably.

 

Your UHD Monitor with 60 Hz, and g-Sync will have G-Sync act ive up to 60 Hz / 60 fps.

If you disable all sync, and your game runs in 80 fps, you will NOT have G-Sync enabled, You will simply have 80 fps on 60 Hz, and with Tearing.

If you have G-Sync enabled, and your fps are BELOW 60, then you will have the perfectly smooth G-Sync experience.

As v-Sync on: If your fps reach 60, it will switch from G-Sync status over to V-Sync status (since you have the full 60+ fps), which MIGHT cause stuttering.

So you usually use an fps-Limiter at 59~.

 

And THIS is supposed to be that way.

Since your Monitor has only 60 Hz, then anything above 60 fps is a complete Waste. you won't see anything. 120 fps on a 60 Hz screen will look exactly as smooth, as 60 fps. The Monitor will just show you every 2nd Frame, and skip every other.

 

So, the ideal for you is, set your settings so you always have around 50-60 fps, or 45 fps or whatever your GPU can handle in your Game, in your prefered Settings.

fps-Limiter is a good way, to keep the fps constant^^

Perfectly even 45 fps lock will feel better and more consistent, than fps-fluctuations between 45 and 60 fps up and down. And g-Sync works at any fps range below 60 (even below 30!)

[Flevor]

4 hours ago, Darkseth said:

G-Sync is an Adaptive Refresh Rate (VRR).

It's a Technology, similar to Freesync, aka Adaptive Sync (from VESA), that is pretty much the opposite of V-Sync ( Vertical Sync).

 

First of all, V-Sync:

Monitor has 60 Hz, GPU is set to Monitor's Refresh Rate. Which means, 60 fps Limit max, and everything above, will stay at 60 fps. This is the optimum here. perfectly smooth 60 fps, with every single Image beein displayed for 16,67 ms duration.

If you fall BELOW 60 fps, THEN you have the Problem: Stuttering.

Imagine it as a simple Math problem. Monitor has 60 Hz, it refreshes 60 times per Second.

V.-Sync forces the GPU to "give" the Image only as a full one (no half-images, like when you have Tearing). As long the GPU is fast enough to render it in Time, everything is good (except maybe a bit Input Lag). If GPu is NOT fast enough, then the Monitor will display the Previous Image again --> It feels like that one image "freezes". It won't stay for 16,67 ms, but 33,4 ms (double as long).

This is stuttering.

50 fps and 60 Hz. How do you fit 50 images in 60 Hz? By doubling 10 of the 50, then you get 60.

 

Now G-Sync: Exactly the Opposite. The GPU pushes out frames, but the Monitor will match the GPU. If the GPU can only render 52 fps, the Monitor will run in 52 Hz.

If the GPU can render 38 fps, the Monitor will run in 38 fps. This changes in realtime without Delay.

This way, you will have no stuttering (because no doubled frames. Monitor refreshes as soon the GPU has the next Frame ready), and no Tearing (because it's "synced"). Also, Input Lag doesn't increase noticeably.

 

Your UHD Monitor with 60 Hz, and g-Sync will have G-Sync act ive up to 60 Hz / 60 fps.

If you disable all sync, and your game runs in 80 fps, you will NOT have G-Sync enabled, You will simply have 80 fps on 60 Hz, and with Tearing.

If you have G-Sync enabled, and your fps are BELOW 60, then you will have the perfectly smooth G-Sync experience.

As v-Sync on: If your fps reach 60, it will switch from G-Sync status over to V-Sync status (since you have the full 60+ fps), which MIGHT cause stuttering.

So you usually use an fps-Limiter at 59~.

 

And THIS is supposed to be that way.

Since your Monitor has only 60 Hz, then anything above 60 fps is a complete Waste. you won't see anything. 120 fps on a 60 Hz screen will look exactly as smooth, as 60 fps. The Monitor will just show you every 2nd Frame, and skip every other.

 

So, the ideal for you is, set your settings so you always have around 50-60 fps, or 45 fps or whatever your GPU can handle in your Game, in your prefered Settings.

fps-Limiter is a good way, to keep the fps constant^^

Perfectly even 45 fps lock will feel better and more consistent, than fps-fluctuations between 45 and 60 fps up and down. And g-Sync works at any fps range below 60 (even below 30!)

Wow thank you that cleared up alot!

 

but it kinda feels like my SLI GTX 1080's performance goes to waste having to lock the fps so low

 

aah well maybe i'll get an higher refresh rate monitor