Why does vsync run so much better with borderless fullscreen than exclusive?

[themanuel]

(10-14-2016, 03:24 AM)Jhonn Wrote: And why exactly you need VSync? GC/Wii games never goes above 60 FPS, so, assuming your monitor has a 60Hz refresh rate you shouldn't experience any screen tearing, even with VSync off...

I don't claim to know the technical details of why this happens but I can assure you, if you play a native 60FPS game that your system can actually run at 60FPS, in exclusive fullscreen mode (without checking the box for borderless fullscreen), you will see screen tearing.

I used to run in borderless fullscreen and let Windows WDM eliminate the screen tearing to avoid the vsync penalty.  However, some games show mild stuttering, even while maintaining 60FPS, per dolphin's FPS counter. However, thanks to a tip I received in the forums yesterday, I've now started using vsync again in exclusive fullscreen mode and I'm no longer seeing a degradation in framerate, nor the aforementioned micro-stuttering.  I don't know if this is because of updates to my video card driver or if using Windows 10 instead of Windows 7 has something to do with that, but I really like my new settings.

[drhycodan]

Yes, Dolphin would say 60fps even when I am seeing 30fps. I do believe that is why most games/emus have a triple buffering option, or automatically turn triple buffering on when vsync is enabled.

[themanuel]

But how are measuring it? What do you mean by "seeing"? Sorry. Not trying to be difficult.

[drhycodan]

With my eyes. It's not hard to see the difference in 60fps and 30fps.

[themanuel]

There must be a system difference. I did a bunch of testing last night on the Metroid Prime (MPT) intro sequence,with and without borderless fullscreen with vsync on and without and could not perceive any difference in performance or smoothness. Of the games I have, this game in this scene is one of the few that doesn't run full speed so I use it a lot for testing.

What I have found lately for my system is that I can run vsync without penalty whereas which didn't use to be the case two years ago. With so much that has changed in Dolphin in that time, me switching to Windows 10 and the updates to the AMD drivers, I have no clue why this is but I'm now happy with vsync and exclusive fullscreen mode. It has helped eliminate some mild micro-stuttering I used to have on scrolling titles like DKCR.

[TehGuy]

(10-14-2016, 03:24 AM)Jhonn Wrote: And why exactly you need VSync? GC/Wii games never goes above 60 FPS, so, assuming your monitor has a 60Hz refresh rate you shouldn't experience any screen tearing, even with VSync off...

IIRC, the Guitar Hero line of games are real finicky/near unplayable (has to do with hit detection for the notes) without Vsync turned on