VSync and triple buffering!

[HUSSAR 258]

Also could you please explain how this could have happened ; the cpu usage reduction i mean ...

 

Have you read this thread Jaffer?

 

http://www.avsim.com/topic/482415-my-version-on-how-to-get-smooth-and-stutter-free-p3d-31/

[SteveW 1,792]

Steve, why the option NVI at 30 and also 30 locked in P3D ?

Hi Gerard,

 

I've demonstrated before that applying the limiter and the fixed rate combine to produce a smoother result. Same as with FSX 1/2 refresh.

 

The fixed rate creates a look ahead buffer that requires a very powerful machine. I know folks say "I'm seeing 45fps can I lock at 40?" You can but it won't work well. If you are seeing 60fps you can lock at 30.

 

But the limiter + Vsync + TB + unlimited is far less taxing. The locked frame rate bangs on creating the look ahead buffer irrespective of refresh or limit, and any stutter will deplete the buffer and it takes good performance to refill it.

[GSalden 4,654]

Hi Gerard,I've demonstrated before that applying the limiter and the fixed rate combine to produce a smoother result. Same as with FSX 1/2 refresh.The fixed rate creates a look ahead buffer that requires a very powerful machine. I know folks say "I'm seeing 45fps can I lock at 40?" You can but it won't work well. If you are seeing 60fps you can lock at 30.But the limiter + Vsync + TB is far less taxing. The locked frame rate bangs on creating the look ahead buffer irrespective of refresh or limit, and any stutter will deplete the buffer and it takes good performance to refill it.

Steve,

 

Tomorrow I am going to try this.

 

At this moment with P3D set to Unlimited I get fps of 27-37 at a very detailed airport with AI traffic and several cloud layers. Unlimited is FFTF = 0.01

With P3D set to 30 that drops to 17-26.

Therefore I am using the NVI limiter set to 25 and my monitors to 25 too.

 

I hope that with setting P3D to 25 too not will drag my fps to below 25 and I will loose the advantage.

[jimcarrel 688]

I tried this setting - Lock to 30 frames in P3D, turn on vsync and triple buffering and also lock frames to 30 in NI. (running 60HZ monitor)

 

Running A2A Comanche with GTN 750, clouds at KJAC I stayed between 29.5 and 29.7 flying thru mountains to the NW.

 

Just prior I was running lock to 30 in P3D, no vsync, no triple buffering and no NI. During same trip I would get 26 to 29 fps.

 

So Steve's recommendations for a "look-see" setting was a bit of a plus for me. One small hitch, I did get a slight pause (almost unnoticeable), but after about 6-8 minutes it seemed to settle down and run better. 

 

I also want to add that with the new settings, things seem "snappier" especially outside viewing. Also forgot to mention that along with GTN 750 I'm running ASN on networked machine.

[TheFlightSimGuy 514]

Ok, so after some testing in P3D v3.2, I have to agree that 30 locked in Nvidia Inspector and Unlimited frames w/ Vsync and Triple Buffering in the sim is the golden ticket for my system. Thanks for the suggestions Steve! 

[SteveW 1,792]

It's good, they've done a lot of work on that at LM guys. You're welcome, thanks for the feedback!

[klamal 282]

Can fps limiting be done via the nvidia control panel at all? I'm assuming not nor can I find any obvious setting there but maybe I'm missing it? So I guess it's time to install NI again and give this a try then.

[SteveW 1,792]

No fps limit is not in the NCP. But anyway, NI won't mess things around used carefully. Always be sure to start from a fresh NI profile especially when we get a new driver... go into NCP and Restore/Apply the Prepar3D profile, this deletes the NI setup. So if we go to NI there will be no Prepar3D profile ready. So before closing NCP, we can make an adjustment in that profile page, like set power management to prefer Max Performance, and making that one change reintroduces a fresh profile in NI. Now close NCP and run up NI, we find a fresh profile in NI.

Setting as low as 30fps or 29fps is possible. Setting lower values of fps requires editing the CustomSettingNames_en-EN.xml found in the NI program folder.

 

..
..
<!-- added -->
        <CustomSettingValue>
          <UserfriendlyName>26 fps</UserfriendlyName>
          <HexValue>0xF000001A</HexValue>
        </CustomSettingValue>
        <CustomSettingValue>
          <UserfriendlyName>27 fps</UserfriendlyName>
          <HexValue>0xF000001B</HexValue>
        </CustomSettingValue>
        <CustomSettingValue>
          <UserfriendlyName>28 fps</UserfriendlyName>
          <HexValue>0xF000001C</HexValue>
        </CustomSettingValue>
<!-- original -->
        <CustomSettingValue>
          <UserfriendlyName>29 fps</UserfriendlyName>
          <HexValue>0xF000001D</HexValue>
        </CustomSettingValue>
        <CustomSettingValue>
          <UserfriendlyName>30 fps</UserfriendlyName>
          <HexValue>0xF000001E</HexValue>
        </CustomSettingValue>
..
..

[glider1 90]

I tried 30NI + VSYNC + TB + UNLIMITED. It isn't the silver bullet for smoothness but it is better. I found I had to increase it to 35NI to make the terrain panning look as smooth as I get with 30FPS in FSX locked to 1/2 Vsync. Why that is I don't know. Any theories?

 

EDIT: By terrain panning I actually mean terrain rotation during a tight turn.

[SteveW 1,792]

I tried 30NI + VSYNC + TB + UNLIMITED. It isn't the silver bullet for smoothness but it is better. I found I had to increase it to 35NI to make the terrain panning look as smooth as I get with 30FPS in FSX locked to 1/2 Vsync. Why that is I don't know. Any theories?

 

EDIT: By terrain panning I actually mean terrain rotation during a tight turn.

By setting the 35 limit for P3D possibly means that it looks better because there's simply less time between frames, and possibly points to an unstable fps underlying the sim compared to FSX. But if you had FSX locked rather than just limited by the 1/2 vsync, it would do better on a 60Hz monitor in exclusive mode any day. What's the CPU and AM used?

[Slayer 190]

Why bother locking vsync if you can't maintain that 30 FPS?? in the case of vsync you will go to the next lower refresh multiple which would be 20 or 15.

[SteveW 1,792]

Yes that's true for avoiding long frames, especially down low at 20. But I'd suggest pulling back sliders and keeping things going faster with P3D, at least 26fps. So with 26 or 35 fps it's not going to coincide with the refresh as often as 20 or 30. P3D doesn't anyway unless using the Fixed setting, you'll see the fps flapping around a lot and needs care setting up with addon exes. But when there's less time between frames it helps a lot. Although I regularly use FSX at 20 Locked and 1/3 Vsync.

[klamal 282]

Can you still use DSR with NI? Does that work with these settings talked about here or is that irrelevant?

[SteveW 1,792]

Works OK. Just stick to low orders of DSR. If the menu isn't tiny, DSR isn't working.

[klamal 282]

So to add, I have an i52500k with a gtx970. Do you think these settings will be good with that hardware? I've read some in the other threads where it seems HT on is beneficial. The i52500k can't do HT. So would these settings matter at all there?