What does a g-sync monitor do when FPS is higher than refresh rate ?

[Jay_42]

As title really. I have 2xGTX980's in SLI, and i'm thinking of purchasing a 144hz g-sync monitor. But in some games I can get anywhere between 150-200fps (left 4 dead 2 for example) with v-sync off. What would the g-sync monitor do when the cards pump out more than 144 frames per second ? Would the monitor just cap the max fps to 144 or would g-sync fail to work at any fps over 144 and hence you would see screen tearing ?

 

Thanks.

 

Edit: also should mention the reason why i'm thinking of getting a g-sync monitor is because in many games like left 4 dead 2 for example, the game(s) is kinda unplayable, because using v-sync introduces horrible stutter and input lag, and disabling v-sync causes massive screen tearing.

[niofalpha]

It won't display out more than 144 FPS (Unless you overclock your monitor). However, i'm fairly sure (Not 100% sure) G-Sync ends up acting like a Vsync if the FPS is above the max refresh rate.

[MrSuperb]

afaik it is capped at 144 with gsync enabled

[The Toaster]

As title really. I have 2xGTX980's in SLI, and i'm thinking of purchasing a 144hz g-sync monitor. But in some games I can get anywhere between 150-200fps (left 4 dead 2 for example) with v-sync off. What would the g-sync monitor do when the cards pump out more than 144 frames per second ? Would the monitor just cap the max fps to 144 or would g-sync fail to work at any fps over 144 and hence you would see screen tearing ?

 

Thanks.

It is the same as Vsync, which caps your monitor. But doesn't have the downside if your gpu does too much work.

If you are getting 50 fps over, turn up the quality. Or if at ultra, downsample.

[Jay_42]

So g-sync would effectively "act" like v-sync, making it so frames per second in general is capped at 144, but it wouldn't introduce the stutter and input lag associated with v-sync ?

[Glenwing]

So g-sync would effectively "act" like v-sync, making it so frames per second in general is capped at 144, but it wouldn't introduce the stutter and input lag associated with v-sync ?

 

You wouldn't get the stuttering, since the stutter with V-SYNC is caused by sudden changes in FPS when you drop below the 120/60/30fps thresholds. That wouldn't happen with G-SYNC. Not sure about the input lag.

[Guest Strangerbob]

You wouldn't get the stuttering, since the stutter with V-SYNC is caused by sudden changes in FPS when you drop below the 120/60/30fps thresholds. That wouldn't happen with G-SYNC. Not sure about the input lag.

 

http://www.blurbusters.com/gsync/preview2/

 

You get the same input lag as if it was vsync @ 144fps/hz which really isnt bad at all.

But if you really want to cut away even that you can cap the fps slightly below the max refresh rate and you have a 100% stutter/tearing free experience with input lag as low as it can go or equal to vsync off (hardware being the only bottleneck).

[Jay_42]

http://www.blurbusters.com/gsync/preview2/

 

You get the same input lag as if it was vsync @ 144fps/hz which really isnt bad at all.

But if you really want to cut away even that you can cap the fps slightly below the max refresh rate and you have a 100% stutter/tearing free experience with input lag as low as it can go or equal to vsync off (hardware being the only bottleneck).

 

Humm, that is interesting, thanks for that link bob. It is quite often source games where I have this issue of both v-sync on and off being unplayable due to stutter/lag or horrible screen tearing. Source engine obviously has issues with nvidia hardware. Because my old rig with ATI Radeon 5870 can run L4D2 on same settings/same monitor/same refresh rate with v-sync off @250fps with ZERO/minimal screen tearing. I've kind of been a mission to find out how it can do that, when a GTX980 can't. The only conclusion I can think of is that AMD hardware is more compatible with source games than nvidia hardware. So much so that even a 5 year old AMD card can deal with screen tearing in source engine games better than a top of the line nvidia card.

 

Anyway, thank you for that explanation bob, that explains it in a way I can understand. So basically g-sync has a split personality really. Behaving and feeling like v-sync is off but still matching the refresh rate to fps. And this is how it behaves when that fps is below 144. But whenever the fps goes above 144, g-sync will start to behave and feel the same as v-sync on, with the same input lag. So in short, you will only see all the benefits of g-sync if your fps in a game never goes above 144.

 

Which is going to be tricky. Since even a single GTX980 can often get more than 144fps in many older games. However I wonder if as you mention bob, whether you could use something like riva tuner statistics sever perhaps, to simply cap the max fps in any game at 140 ish ? Would that achieve a 100% stutter/tearing free experience with input lag as low as it can go or equal to v-sync off ?

[Guest Strangerbob]

Humm, that is interesting, thanks for that link bob. It is quite often source games where I have this issue of both v-sync on and off being unplayable due to stutter/lag or horrible screen tearing. Source engine obviously has issues with nvidia hardware. Because my old rig with ATI Radeon 5870 can run L4D2 on same settings/same monitor/same refresh rate with v-sync off @250fps with ZERO/minimal screen tearing. I've kind of been a mission to find out how it can do that, when a GTX980 can't. The only conclusion I can think of is that AMD hardware is more compatible with source games than nvidia hardware. So much so that even a 5 year old AMD card can deal with screen tearing in source engine games better than a top of the line nvidia card.

 

Anyway, thank you for that explanation bob, that explains it in a way I can understand. So basically g-sync has a split personality really. Behaving and feeling like v-sync is off but still matching the refresh rate to fps. And this is how it behaves when that fps is below 144. But whenever the fps goes above 144, g-sync will start to behave and feel the same as v-sync on, with the same input lag. So in short, you will only see all the benefits of g-sync if your fps in a game never goes above 144.

 

Which is going to be tricky. Since even a single GTX980 can often get more than 144fps in many older games. However I wonder if as you mention bob, whether you could use something like riva tuner statistics sever perhaps, to simply cap the max fps in any game at 140 ish ? Would that achieve a 100% stutter/tearing free experience with input lag as low as it can go or equal to v-sync off ?

 

If you manually put up a global fps cap of 130 (to make sure, cuz according to those tests you need a few more fps lower than just 140), you will get a total tear/stutter/input lag free gaming. The only thing required of you then is to have the fps higher than 40.

 

Its a rarely, but still known trick that you could turn vsync on with your average 60hz monitor and cap the fps @ 59. To get no tearing and no input lag. But you got microstutters, which was still the best you could do before gsync.

[Jay_42]

If you manually put up a global fps cap of 130 (to make sure, cuz according to those tests you need a few more fps lower than just 140), you will get a total tear/stutter/input lag free gaming. The only thing required of you then is to have the fps higher than 40.

 

Its a rarely, but still known trick that you could turn vsync on with your average 60hz monitor and cap the fps @ 59. To get no tearing and no input lag. But you got microstutters, which was still the best you could do before gsync.

 

Ok, will do. Thanks bob. Thanks to everyone else too, your input has really helped me get my head around some of the eccentricities of g-sync.

[storm trooper]

i can answer that for you as i have one..you have to put a cap on your game that goes over 144fps..otherwise you will get tiny screen tearing g-sync only work no higher than 144fps..after that it's like no g-sync at all..But be carefull in 3d setting coz when enable g-sync in the monitor options..v-sync will be enabled as well..that seems to be the default setting that nvidia has set..so you must scroll down click v-sync off....so if you have a 144hz monitor..and you run games OVER 144fps like i do as i have two gtx 970 SLI....at 200fps in bf4 with v-sync off and g-sync on...it wont look very good little mico tears when looking at trees trucks and such and moving the mouse really fast....So i did a GameTimeMaxVariableFPS 140...and now WOW!!...you can see g-sync working..big difference straight away...so all in all you MUST cap your fps to 140fps IF you always going over that mark....all ways leave v-sync off as well

[m_tieu]

You now have the option to have vsync on to cap the frame rate at the upper limit of your monitor or you can have vsync off and let it render more frames per second than the monitor can refresh and have tearing like a non gsync monitor but reduce input lag.