[Thread Superseded] G-Sync 101 w/Chart (WIP)

[kingbenjie]

@jorimt

Yes my second monitor is at 60hz vs my gaming monitor of 165hz. Well I'll keep playing around with the settings to see if I find a fix. BTW, I'm still loving the recommended settings for my setup. It's like the secret sauce for perfect butter lol.

KB

[drmcninja]

So I got Fast-sync working in Overwatch!

I disabled Windows Game Mode, Game Bar, basically everything in that menu and also everything within the sub-menus. So I unchecked 'Open Game Bar using this button on a controller' and 'Show game bar when I play full screen games Microsoft has verified', and kept everything off in every menu. I also made sure GeForce Experience's 'Share' was disabled (so their Alt+Z overlay was also disabled).

Then I tried Fast-Sync and noticed my framerate would randomly cap at 240-something, 250-something, and 260-something fps (hard to tell exactly which number because it fluctuated). It was really weird since my in-game fps cap was 300 (verified as working at 300 before doing this). In any case, I didn't see any tearing.

So why does Fast-Sync cap at these seemingly random numbers? My refresh rate is 120Hz btw (Lightboost 10%). My bet is it's some function of the refresh rate and in-game FPS.

Feels great! More responsive than V-Sync @ 119fps/120Hz (I'm guessing since Fast-Sync is slightly less laggy than V-Sync and the higher FPS has less input lag?).

[drmcninja]

My G-Sync isn't working if I have vsync on + gsync, but fps never goes over 159 fps, or is it?

Does turning on G-Sync do something to nullify the V-Sync input lag? I don't see how else G-Sync ON, V-Sync ON would have less lag than just V-Sync ON, with both set to -2 fps below Refresh Rate.

With g-sync the start of the refresh cycle stays synchronized with frame completion, so on average it will be half a frame lower latency than vsync without g-sync. Assuming both are capped below the refresh rate.

Does the same hold true if pairing G-Sync ON with Fast-Sync?

[drmcninja]

Nevermind to that... enabling G-Sync and Fast-Sync simultaneously caps fps to refresh rate for some reason. Even though just G-Sync ON with no Fast-Sync and no V-Sync allows FPS to be uncapped. And just Fast-Sync with no G-Sync also lets FPS exceed refresh rate. But together, apparently not.

[RealNC]

It should be noted that g-sync + fast sync makes no sense if you're frame capping to get rid of latency.

[drmcninja]

It should be noted that g-sync + fast sync makes no sense if you're frame capping to get rid of latency.

No, I was thinking of just Fast-Sync, fps uncapped, with G-Sync to perhaps get rid of half a frame of input lag like it does with V-Sync.

[jorimt]

Then I tried Fast-Sync and noticed my framerate would randomly cap at 240-something, 250-something, and 260-something fps (hard to tell exactly which number because it fluctuated). It was really weird since my in-game fps cap was 300 (verified as working at 300 before doing this). In any case, I didn't see any tearing.

So why does Fast-Sync cap at these seemingly random numbers? My refresh rate is 120Hz btw (Lightboost 10%). My bet is it's some function of the refresh rate and in-game FPS.

If you're at 120Hz, then it looks like Fast Sync is auto regulating at roughly 2x your refresh rate (240 FPS). It would be at a 3x ratio or higher if Overwatch didn't have a 300 FPS limit, and if you could sustain framerates in that range. Working as expected.

Nevermind to that... enabling G-Sync and Fast-Sync simultaneously caps fps to refresh rate for some reason. Even though just G-Sync ON with no Fast-Sync and no V-Sync allows FPS to be uncapped. And just Fast-Sync with no G-Sync also lets FPS exceed refresh rate. But together, apparently not.

Wait, do you have a G-SYNC monitor?

G-SYNC + Fast Sync is not recommended; It does some strange things, even inside the G-SYNC range. This will be detailed in my article releasing Monday.

[jorimt]

Update 06/19/2017:
Blur Buster's complete 4-part "G-SYNC 101" series has been released on blurbusters.com:
http://www.blurbusters.com/gsync/gsync101/

This topic has been closed, but will remain visible for archival purposes.

Please continue the discussion here:
http://forums.blurbusters.com/viewtopic.php?f=5&t=3441