Gsync vsync lag with dolphin

[hexism]

Not sure if this is the correct place to ask this, but I was wondering why I feel considerable more input lag when playing Melee on dolphin emulator with gsync and vsync enabled on nvcp, compared to gsync with vsync off. I use a 360hz alienware, and the game is capped at 60fps, so vsync shouldn’t be adding any additional lag correct? Is it just vsync not behaving well with dolphin/melee? Sorry if this post is redundant/already been answered before.

[RealNC]

Are you sure the display is actually running at 360Hz when running Dolphin? Check the monitor's OSD for what the current display mode is.

[hexism]

Yeah to my knowledge it should be running g-sync @ 360hz, the osd shows 60hz because 60fps on dolphin though.

[roro13200]

yes but dolphin is at 60fps, he will see 60hz with gsync in the osd.
Nope ?

[jorimt]

Yeah to my knowledge it should be running g-sync @ 360hz, the osd shows 60hz because 60fps on dolphin though.

Most monitor OSDs have a readout separate of the real-time VRR frame/refresh rate meter that shows the actual current max physical refresh rate. Mine does.

For instance, my monitor's G-SYNC meter will show as "60" in a 60 FPS game:



But the overlay will show 2560x1440@240 Hz:



If I have it improperly configured and/or the game or app is also forcing my physical refresh rate to 60Hz in G-SYNC mode for whatever reason, then I will instead see 2560x1440@60 Hz, which is what you don't want.

[hexism]

I have the Alienware aw2521h, it doesn’t seem to have that option just the current hz. I don’t think dolphin is forcing 60hz g sync either because it feels fine when all settings are the same except vsync off.

[jorimt]

I have the Alienware aw2521h, it doesn’t seem to have that option just the current hz. I don’t think dolphin is forcing 60hz g sync either because it feels fine when all settings are the same except vsync off.

I looked up your monitor's manual. From what I can tell:

1. AW2521H OSD > Others > Display Info > Current shows the current maximum physical refresh rate.
2. AW2521H OSD > Game > Game Enhance Mode > On shows the current real-time refresh/framerate in G-SYNC mode.

In G-SYNC mode, you want #1 at 360Hz, and you want #2 at ~60 FPS (or whatever the current Dolphin game's native framerate is).

As for G-SYNC on + V-SYNC on vs. G-SYNC on + V-SYNC off, the only latency differences within the refresh rate (where 60 FPS is already 300 frames within the G-SYNC range at 360Hz) is tearing.

I.E. visible tearing is only latency reduction between the two, so if you think you're experiencing any other form of latency with G-SYNC on + V-SYNC on vs G-SYNC on + V-SYNC off, it's likely either placebo, or G-SYNC isn't actually engaged in Dolphin and you're toggling standalone V-SYNC, which can feel notably laggier than off.

Make sure G-SYNC is actually active. Also verify that you are running Dolphin in fullscreen and not borderless mode.

[hexism]

Hmm okay yeah the current shows 360hz and the game enhance shows 60hz, so gsync is enabled and it’s checked for just fullscreen, same with dolphin, fullscreen with no vsync, just nvcp vsync. It definitely isn’t placebo I can feel a difference in my inputs, I can’t hit tech that I can with it off.

[jorimt]

Hmm okay yeah the current shows 360hz and the game enhance shows 60hz, so gsync is enabled and it’s checked for just fullscreen, same with dolphin, fullscreen with no vsync, just nvcp vsync. It definitely isn’t placebo I can feel a difference in my inputs, I can’t hit tech that I can with it off.

Then with that all ruled out, and assuming G-SYNC is indeed engaged, the issue may be specific to SSBM. I don't even remember if it was synced on the original console. If you're using netplay that could also be a factor.

Basically, Dolphin emulation of a twitch game like SSBM with or without netplay is a fringe scenario for G-SYNC, and for all we know additional buffering issues could be triggered when the V-SYNC flag is enabled for that game in certain situations, regardless if G-SYNC is enabled.

As such, feel free to play with G-SYNC on + V-SYNC off or G-SYNC off + V-SYNC off in that particular game if it feels better for you.

[hexism]

I've been stumped as to why it feels different for a while now, I've asked on the slippi/dolphin discord too, I imagine it's as you say, something must be funky with its implementation. Thank you for the help!