A possible solution to FPS and stutter probs for NVidia users

Hiya, trying to avoid unnecessary blethering so I'll keep this terse. Anyway, my latest research into this points to the following solution - getting stable 30FPS and no stutters even with MANY* rocket salvos now:

 

1) Only works if your screen refresh rate is 60Hz, all others use refresh rate / 2

2) graphics.cfg MaxFPS = 30

3) NV Inspector FPS limiter = off

4) NVI vertical sync tear control = standard

5) NVI vertical sync = 1/2 refresh rate * IMPORTANT - gotta have this for smooth operation at 30FPS*

 

Thoughts?

 

PS / EDIT: Also see the link in the next post for other tweaks I'm using in combination with this, AND DO NOT THINK THIS IS A PANACEA FOR ALL DCS FPS ILLS. But these tweaks work pretty well for me regardless...

* is an edit, was "most" but let's not get too carried away shall we ;)

Edited February 3, 2013 by msalama

My thoughts are that you are experiencing placebo effect. If you fire full rocket salvo of say 4x UB-8 rockets and your FPS doesn't dip bellow 30fps as you say I would be interested in more... but I am sure you will get very low FPS in this scenario... maybe you should test properly and record FPS using FRAPS?

My thoughts are that you are experiencing placebo effect.

I'm not. But as I said this pertains to MANY* rocket salvos, not all, and f.ex. Smerch and many cluster munition launches still slow things down considerably. I've not experienced any great FPS slowdowns from aerial rockets after upgrading my computer anyway, and the settings here combined with tweaks I've presented elsewhere (see http://forums.eagle.ru/showthread.php?t=101083) really DO help in getting smooth and stutter-free gameplay. YMMV, of course, which is why I asked for your thoughts and opinions - but placebo these settings ain't Sir, I guarantee you that ;)

 

I'm sorry I'm bad at explaining things, and now realize that I should've come up with a link to those other tweaks in the 1st post already, because this all kind of works in combination of course. But to expand on my thinking behind this, what I'm shooting for is the lowest common denominator of sorts as it comes to achievable constant framerate and/or minimizing stutters - and capping the sim at 30 f/s works perfectly, because my FPS very seldomly goes below that, AND conveniently also happens to be at 1/2 screen refresh rate, which is also very important for reducing stutters because one needs to sync everything to the screen in order to achieve a smooth data flow through the system.

 

I first tried to limit the FPS in the driver, but found out that this hiccups every now and then, because that presents an external "throttle" on the sim rendering pipeline. But that all went away after I thought of limiting the framerate INTERNALLY in graphics.cfg and then locking the card / display to this value, because what that achieves is a push-pull mechanism of sorts i.e. the sim puts out stuff to its best ability at any given moment and the video / display part of the chain is "slaved" to that. Now this obviously DOESN'T work when things slow to a crawl, but situations like that are an exception for me anyway, i.e. said 30FPS is what I'm seeing like 90+% of the time.

 

I again apologize for my rambling style in trying to explain things. But the hell with it, just try this and if things turn to garbage just junk it :P Still hope this is of general help though...

 

* edited - was "MOST" but again let's not be snake oil salesmen shall we ;)

Edited February 3, 2013 by msalama

What do you mean by Aerial rockets? And yes, any air-to-ground rockets in larger quantity (ie UB-16, UB-32, UB-8 etc where there are larger quantities of rockets in pod container) do cause massive FPS drop no matter what system or settings you have/use... it's simply due to shader coding not being efficient... which is why I posted I am surprised if you had no FPS drop using salvo of these rockets (or cluster weapons etc).

 

I am also well aware of FPS limit in Graphics/cfs, I recommended using it many years back and have been using this for years and there are more tweaks you can have to get bit better FPS (which I have again posted few times in different posts and people still haven't cought up on it - it's mostly with distances you can adjust, but I won't comment more since most don't care about it and are happy with default values)

 

Just that you really need to be careful when you start claiming you get steady 30fps just by using some driver setting as I've seen so far every time someone posted something like this is not really living up the claim (as you said in your second post, you still get FPS drop using clusters etc, which is the whole point of trying to eliminate this drop) so if you come up with something that can get clusters and salvo of rockets not cause a drop, I am all ear but this ain't it :)

Hmmmmm interesting. I have a 4GB 680 incoming in the next week or so and will test this.

 

Ta :)

just by using some driver setting

Not JUST by a driver setting, see my 2nd post where I explicitly state that other tweaks are in play as well (and apologize for not having been clear on this right from the start).

 

which is the whole point of trying to eliminate this drop

Umm, no, not the WHOLE point by far. These tweaks also all but eliminate microstutters as well I've found - used to get this annoying "hiccuping" when looking sideways from the cockpit, but not anymore.

 

due to shader coding not being efficient

OK, gotta come clean on this I think, because I'm actually using some shader files from BS1 as well and that seems to help some too.

 

But no, this ain't no panacea, you're absolutely correct in that regardless. But that still doesn't take away from the fact that the sim is running VERY smoothly for me now that I've done all of the above...

 

any air-to-ground rockets in larger quantity

Believe it or not, most garden variety a-to-g rockets cause no FPS headaches for me now (this might have to do with said BS1 files, I dunno)
Edited February 3, 2013 by msalama

So Kuky, think "lowest common denominator" and everything sorta slaved to that and you'll see what I'm driving at.

Edited February 3, 2013 by msalama

How about post what shaders from BS1 you are using, might be worth trying them out

At yer service good Sir, here goes :) These are the files I've pinched from BS1 judging from the timestamps - don't have BS1 installed ATM so not sure if I've left something out however:

 

Bazar/Effects/PFX/High/*

Bazar/Effects/Explode/Cluster/High/*

Bazar/Effects/Explode/FireSmokeOne/High/*

Bazar/Effects/Explode/FireSmokeOneMiddle/High/*

Bazar/Effects/Explode/FireSmokeOneMiddleZero/High/*

Bazar/Effects/Explode/FireSmokeOneShort/High/*

Bazar/Effects/Explode/FireSmokeOneShortZero/High/*

Bazar/Effects/Explode/Ground/High/*

Bazar/Effects/Explode/Napalm/High/*

Bazar/Effects/Explode/SimpleGround/High/*

Bazar/Effects/Explode/SimpleSky/High/*

Bazar/Effects/Explode/Sky/High/*

Bazar/Effects/Explode/SkyDirect/High/*

Bazar/Effects/Explode/SmokeCloud/High/*

Bazar/Effects/Explode/SmokeOneGray/High/*

Bazar/Effects/Explode/SmokeOneWhite/High/*

Bazar/Effects/Explode/SmokeOneWhiteShort/High/*

Bazar/Effects/Explode/SmokeOneWhiteZero/High/*

Bazar/Effects/Explode/StartRocket/High/*

Bazar/Effects/Explode/TankShot/High/*

Bazar/Effects/Explode/Water/High/*

Bazar/Effects/Explode/Volume/High/*

Bazar/Effects/RenderEffects/Shaders/*

 

And that's pretty much it I think.

Can you put all these files (that you are using from BS1) in an archive (WinZIP or WinRAR) and attach (if it's not too much trouble)? I don't have BS1 files but would like to try them out in latest DCS World

Edited February 3, 2013 by Kuky

Certainly, was about to release these as soon as got me arse in gear anyway :) See here: http://forums.eagle.ru/showthread.php?p=1667399

Thanks

I found that 30fps (or anything other than monitor Hz) will have the terrain flickering (a bit like an old movie reel)

I found that 30fps (or anything other than monitor Hz) will have the terrain flickering (a bit like an old movie reel)

 

That can happen, yes, although it should disappear when you get higher. Did you use NVI's 1/2 refresh rate option when you tried it?

 

I'd like to have a higher FPS limit, but if I cap it at, say, 60 in order to sync it 1:1 with my Acer I get irregular stuttering when the framerate falls below. But a 30 f/s lock with a 1:2 sync works very well, because the framerate stays above 30 pretty much all the time, meaning there're no bottlenecks at that rate and thus no stutters either - well apart from said regular flickering / juddering down low! But that doesn't really bother me too much because it's REGULAR

the 30FPS MAx also works on AMD Cards,

the 30FPS MAx also works on AMD Cards

 

Right Zilla. The crux of the matter, as I see it, is as follows:

 

1) Pick a framerate that your system holds up consistently AND that either matches or is a quotient of your monitor's refresh rate (i.e. 120, 60, 30).

 

2) Force vertical sync on at 1:1 or 1:2 or 1:3 refresh rate, depending on which quotient of the refresh rate your selected framerate falls on.

Edited February 4, 2013 by msalama

 

But a 30 f/s lock with a 1:2 sync works very well, because the framerate stays above 30 pretty much all the time, meaning there're no bottlenecks at that rate and thus no stutters either - well apart from said regular flickering / juddering down low! But that doesn't really bother me too much because it's REGULAR

 

 

 

 

so its not really a proper soultion then, eh...

AMD Drivers have broken "Global" VSYNC for a while now

@msalama: Setting FPSMax at 30 is not needed when you set the VSync rate at 1/2 of the monitors refreshrate (if it's a 60Hz one). So you can leave out point 2. Same goes for point 3. As long as you don't set it below 1/2 of the refreshrate and you use VSync at 1/2, this option is useless.

 

I did quite some digging in this matter because when switching from a CRT monitor to an LCD, i noticed microstuttering below the monitors refreshrate when using an LCD (the CRT has that too but due to the slow respons time of the screen, you don't notice it). The microstuttering starts the moment your FPS drops below the monitors refreshrate. Let's that it has refresh of 60Hz.

So the moment you hit 59Hz, the microstuttering starts and this gets worse and worse up until you hit 1/2 of the refreshrate, 30Hz in this case. The all of a sudden it's all smooth again although you notice a difference between 60 and 30 FPS for sure. 60 is a lot smoother.

The moment your FPS drops below this 1/2 rate again, microstuttering starts to show up again.

This sort of microstuttering is mostly visible when the world outside moves very fast and when you look at it under a 90° angle (looking either left or right). It's also visible in forward view but less pronounced until you hit lower FPS numbers just above 1/2 VSync.

As you mentioned, you can stop this by setting the VSync to on if you know your FPS will not go below that threshold and set it to 1/2 if you can't keep it steady at 60 with a slight drawback that it is a bit less smooth.

 

@Wolf Rider: When FPS is limited to 30 through either MaxFPS or VSync, make sure your MFCD's are set to "every frame" because othewise, with an FPS of 30, these will drop to an FPS of 15 and they will show a lot of microstuttering. It's almost not noticable on the TAD screen but definitely on the TGP or MAV videoscreens. If you set these to every frame and then set overall FPS to 30 (to prevent hickups above that rate), your motion will look a lot more fluid. And if you keep it running like that for a longer time, if will feel smoother then in the beginning. Until you start switching again back and forth between 30 and 60 FPS.

 

For those interrested:

 

- How VSync works.

 

- The Gamer's Graphics & Display Settings Guide (page 5, 6, 9 and 10 are most important regarding this discussion)

this option is useless.

 

It's true that syncing at 1/2 refresh rate on a 60Hz flatscreen already limits frames to 30. But why pump out more frames than you need? Although limiting the frames to 30 in the sim could also work as an unnecessary throttle, and we definitely don't want those...

 

Gotta think on this a bit more & experiment, thanks :)

so its not really a proper soultion then, eh...

 

It is if you want to get rid of irregular stutters, which I personally can't stand. But it's not a panacea to all DCS ills, nossir, not at all.

this option is useless.

 

Strange as it may sound, the microstutters are back if I put MaxFPS to zero. This may be because the sim then produces more f/s than 30 and thus creates a bottleneck by somehow "pushing" against the driver's 1/2 refresh rate limit, I don't know? Hmmm...

set your frame per render to 4 on 580's and above. :thumbup:

call me old school...

 

I too get the shudders and stutters after @ 4 hours of flight. I have tried some of the cures offered up and they work for awhile... but after @ 4 hours of flight I get the stutters again. So, I de-frag. And then I have @ 4 hours of stutter free flying.

 

Old school? Stupid newbee? Old guy with no idea whats going on? I'm open to all of this and more, but a de-frag really seems to clear all this up!

 

at least for me!

 

@Wolf Rider: When FPS is limited to 30 through either MaxFPS or VSync, make sure your MFCD's are set to "every frame" because othewise, with an FPS of 30, these will drop to an FPS of 15 and they will show a lot of microstuttering. It's almost not noticable on the TAD screen but definitely on the TGP or MAV videoscreens. If you set these to every frame and then set overall FPS to 30 (to prevent hickups above that rate), your motion will look a lot more fluid. And if you keep it running like that for a longer time, if will feel smoother then in the beginning. Until you start switching again back and forth between 30 and 60 FPS.

 

 

which goes back to my point of (old movie reel) terrain flicker.

A smooth cockpit maybe one thing, but the terrain is seen to flicker from that smooth cockpit...

It s not a matter of 'well don't look at it then :) '... its there it can be seen

 

 

"irregular stutters" are usually file loadings.