What is the general practice for Framerate Limiter and Direct3D Settings?

[galumn]

First, I have to apologise if this has been asked numerous times before, I just cannot find definitive answers; txt file in Readme folder does not explain them and Special K's page on pcgamingwiki does not goes into details on how to set each values.

I just found out about Special K, like a couple weeks ago, when I bought Tales of Vesperia. And it works beautifully with that game using game-specific recommended settings.

So, I want to try to use Special K with other game as well, hoping to get smoother gameplay experience. I tried using the same setting with Super Lucky's Tales. The game play doesn't turn out to be as smooth as Tales of Vesperia.
And when I look at frametime, Tales of Vesperia will always appear as straight green line, but Super Lucky's Tales will show wavy yellow line.
https://i.imgur.com/3NkH69a.jpg

These are what I gathered from Google search:
- Flip Model Presentation is preferable for modern Windows OSes.
- to use Flip Model Presentation, Borderless fullscreen windowed mode is needed.
- Value of Presentation Interval should be '1' so game's framerate would sync with monitor's refresh rate.
- Waitable SwapChain helps reduce input latency but it does not work well with Steam Overlay.

So my questions are:
1. Is it recommended to turn Framerate Limiter on?
Like, if I only have regular monitor that capped at 60 Hz. I should always turn limiter on right? Since it would be pointless for game to produce more frames than what my monitor can display.

2. In general, what would be recommended value for Target Framerate Tolerance?
Is default value of 2 is ok? I tried changing it to Tales of Vesperia value (4.5), but I couldn't notice any differences.

3. In general, what would be recommended value for BackBuffer Count?

4. I recall reading that the value of Maximum Device Latency is the value of BackBuffer Count + 1. Is that information still true? If not, what would be recommended value for Maximum Device Latency?

5. When should I use Waitable SwapChain? In general, should this option be enabled or disabled?

6. Is it still advisable to disable Steam Overlay while having Waitable SwapChain enabled?

By the way, here is my PC spec:
OS: Windows 10 64-bit Version 1809
Processor: Intel Core i5-9600K @ 3.7 GHz
Memory: 32 GB RAM
Graphics: Nvidia GeForce RTX 2070

[Aemony]

Personally, I just leave all the stuff at their default value. If the FPS limiter is unable to retain a perfectly straight line at 60 then I try lowering it a bit to 59.94 (Ctrl+click on it to input value directly) as the most likely cause it’s unable to work properly is because it’s fighting the default frame limiter of the game.

I also have a G-Sync monitor though so I never have to account for V-Sync, which is its own FPS limiter.

[JBeckman]

Default is good though flip model override doesn't hurt to try if it works though it comes with the limitation of requiring a fixed resolution so it shouldn't be changed once you've set it up in SpecialK.

The OSD will show the resolution used as well in the corner of the main window and hovering over this should show additional information which will also tell if it's using Flip Discard or something else. :)

There was a mini-guide somewhere for flip model but yeah back buffer count to 3 and then pre-rendered frames to 4 or back buffers +1 for this setting.


I generally run with VSync disabled (Don't really notice tearing much.) and a FPS cap so I haven't experimented very much with the newer SpecialK features and flip model for this though in general almost all of the D3D11 titles I did test did boot up without crashing so it seems to work fairly well in most cases at least for the initial compatibility and start up when these overrides are in place.

In addition to a FPS limiter there's also a background FPS limiter though it depends on how you use software, I prefer to alt-tab a bit during longer loading sequences and some games have FPS = loading speed so a low value here can be detrimental.


I guess NVIDIA and AMD drivers can also interfere a bit with the optimal setting since for NVIDIA the low-latency option sets the render ahead value to 1 and for AMD their newer drivers enforce a value of 1 though that's not something I've looked into much at all besides learning more on what and how these driver options and behaviors work and what they actually do though that's also pretty minimal at the moment for what I've learned.

Then there is G-Sync and for AMD FreeSync which I think also changes how the options here work but flip model is still compatible.
(Think the pre-render frame value was something like a buffer so 4 or 5 might be good values too in these cases though I suppose that's down to user preference and just testing and comparing.)


Can't say much on the waitable swap chain or the Steam overlay although for the overlay it still loads unless you rename the actual .dll file so any compatibility issues can still be a concern even after disabling it in the Steam client and some functionality depends on it which for SpecialK I think it draws on the gamepad functionality and it also overrides some of the screenshot functionality if these options are enabled.


EDIT: Hmm as for overriding the big impact would be on frame latency and frame time from what I know, getting less delay and latency and hitting closer to the preferred timing of 33.3ms for 30 FPS and 16.6 for 60 FPS or lower at higher framerates.
(As it is though some games in 2019 are still 30 FPS capped or 60 FPS capped and not easily overriden and when they are it can break things badly having many systems tied to framerate.)

Less time to get a response from having less steps in the whole flip model process, kinda like a chain or how would one describe it but shortening the links a bit so when it works it's pretty good though not everything is compatible but it doesn't hurt to give it a try although I don't really know the particular settings and such very well myself so the explanation is a bit so and so.



EDIT: Oh and when supported SpecialK can now utilize the multi media class scheduling functionality for the framerate limiter which should help with how it works from lessening any CPU impact for how the threading is handled to being more precise and updating and trying to maintain the settings.

Not sure if there are any drawbacks, might look like the CPU is doing more but activity as such isn't a negative and then there's compatibility with earlier versions of Windows but Win7 isn't entirely supported in the current version as is though a number of updates for the OS might help or it might not. (It tends to vary heavily from one major version of SpecialK to the next really.)

EDIT: Well it wouldn't work if MMCS is disabled.
(Not sure what the popular OS tweaks are and software applying a range of settings so just to mention it.)

[galumn]

Aemony, JBeckman, Thank you very much for your inputs.

It turns out that VSync really is the cause.

After I turned VSync off, both in game settings and in Special K (PresentationInterval=0), the game's frame time is significantly improved.
https://i.imgur.com/GmxAoMZ.jpg
Stutters have largely disappeared. There are a few small framerate hiccups here and there but I think it's most likely related to asset loading when entering new zone.

As a regular gamer with basic computer knowledge, I really have no idea why VSync works with Tales of Vesperia but not with this game. I've always thought VSync is what make game run smoothly.