1/2 Refresh Vsync Broken -- latest Nvidia Inspector (2.1.3.20)

Hi there guys,

I recently downloaded the latest Nvidia Profile Inspector, but I'm having a lot of trouble getting the 1/2 Refresh Rate Vsync to work.

For some context, I'm on the latest build of Windows 10 and my Nvidia Drivers are fully up to date via (Nividia GeForce driver downloads/installation).

I've tested DOOM (2016) and Dark Souls III along with some other titles and no games I've tried applying the 1/2 Refresh Vsync work correctly -- all launch and run at 60 fps.

To verify this, I've run Rivatuner Statistics Server (without a framerate cap) to view what fps the games run at.

When I look at the games in question in the Nvidia control panel, the Vsync section for each game reads "Custom" so it does appear the 1/2 Refresh Vsync is getting applied, but the game is ignoring it and it doesn't work.

I've tried resetting back to the default Nvidia Control Panel settings then only setting the 1/2 Refresh Vsync, but that doesn't work either.

It's bizarre because previously the 1/2 Refresh Vsync seemed to be working then suddenly it just stopped.

Has anybody else experienced this issue or know a way to fix it or is this just a problem that exists right now that will be rectified down the line?

Thank you for your help and time, I appreciate it.

- Stephen Enzor

P. S.

I'm aware from reading online that a reboot used to fix this issue or disabling full-screen optimizations perhaps, but neither has fixed the problem for me. 1/2 Refresh Vsync in Nvidia Profile Inspector simply doesn't work for me despite my efforts thus far. Thanks again for your time, any information regarding this issue would be greatly appreciated.

UPDATE:

It would seem that the more official "Adaptive Vsync (Half-Refresh Rate)" from the Nvidia Control Panel is also failing to work since when it's forced, games continue to launch at 60 fps.

In light of this, I'm beginning to wonder if this is an issue with the latest builds of Windows 10 or the most modern Nvidia Drivers -- though I'd be more inclined to suspect Windows 10 as Nvidia has this option officially in it's Control Panel. I had read somewhere that in the past there was some issue with a display driver, but I'm not really certain what's going wrong atm. Thanks again for your time.

 

May I ask why you use 1/2 Vsync?

 

It's used in cases where you want to use an FPS cap of half your refresh rate. Without 1/2 vsync, you get some microstutter due to repeat frames (and a repeat frame at 30FPS is 33ms long, which is a somewhat glaring hiccup.)

1/2 vsync will prevent that from happening.

 

I see, thanks for clarifying it @RealNC

Wasn't aware that lowering fps in that case with rivatuner/inspector would cause micro stutter.

 

@cryohellinc

As RealNC clarified, a 1/2 Refresh Vsync through inspector solves the issue of microstutters when you're game is capped at 30 fps.

Additionally, my understanding is it's required to make use of the Low-Lag Traditional Vsync technqiue of capping under by 0.01-0.1 fps detailed by BlurBusters/RealNC in some other posts.

My rig isn't as modern as it used to be and so for some newer games, to hit native resolution/medium-high settings, my best option is to implement a 30 fps cap similarly to how it's done on console which involves implementing a 1/2 Refresh Vsync with a Rivatuner Framerate cap + an Nvidia Control Panel "Max Pre-rendered Frames" setting of 1 (the minimum) to reduce latency.

Regrettably, all of this doesn't work well enough without the 1/2 Refresh Vsync which at the time of this writing appears to be broken.

 

Maybe re-install the drivers, and this time check the "clean install" checkbox. Maybe this will help.

 

@RealNC

Thanks for the heads-up, I'll give it a go.

This will be the second time I've clean installed the latest drivers though as initially when I'd first installed them was a clean installation.

In light of that, I don't have high hopes a clean installation will solve the issue, but I'll post back here with the results later tonight once I'm home from work and able to give it another shot.

 

@RealNC

UPDATE:

I found a temporary fix that has to be done each time one wants to play a game in 1/2 Refresh Vsync. Thanks for your advice, it led me to this solution.

Basically what I'm able to do is go into Nvidia GeForce -> Reinstall Drivers -> Express Installation (to save my current control panel settings -- SLI + Max Pre-rendered Frames = 1).

This seems to fix the issue albeit temporarily -- after some time the games stop launching with the 1/2 Refresh Vsync and it becomes treated like normal Vsync. I've still yet to determine what occurs that triggers this "breaking".

Anyway, thanks for your time, I appreciate it.

 

Narrow down the issue, you mentioned now you use SLI.

Try to take out one card, run the same setup + default settings and 1/2vsync. Will the issue re-occur? If yes, it's not SLI, if not then you have found your problem.

 

Ah, alright -- I'll give that a shot. I'm not positive yet what exactly is breaking it, but after talking with some others/reading more online about this issue (it's common it would seem), the issue might be related to chrome or the hardware acceleration used there. I can't confirm that yet -- I'm speculating based on the digging others have made. I'll post here again once I learn more since even in other circles exactly what's causing this is a bit up in the air.

Some others mentioned a faster solution than reinstalling the drivers might be restarting them -- however, in that thread it wasn't specified which driver(s) to reinstall so I haven't been able to test that at this point.

EDIT: should be -> "driver(s) to restart" not reinstall, oops

 

Well thats simply a mitigation, and not a solution.

 

Not related to Vsync...

How safe is it to OC with Nvidia Inspector? I bumped core and memory on my GTX 960 quite a bit, and so far it seems stable. Been playing Battlefield 1, Metro Last Light Redux, PES 18, Destiny 2, Overwatch, and temps were as high as 70 degrees, maybe 2-3 above depending on the game. No freezes, artifacts or PC restarting. Haven't touched "over voltage" slider, only bumped temperature limit from 80 to 90 degree. Here is a screenshot of Nvidia Inspector overclock screen:


Should I touch Power limit, maybe increase it? Or did I even did this properly so far? Haven't really overlocked GPU before, only CPU.
P.S. I did +10 or +20, and then checked temps in game, and if everything was ok, i bumped it up a bit more. I haven't bumped it by that much all at once. Just so you know.

 

For me works disable fullscreen optimization for .exe file, thanks for the tip
win10 17134.165 and 397.31 drivers